I hope this review does not come across as a one watch is better than the other watch. I own both of them and like them equally for different reasons but the problem with doing comparative reviews is that there is always a tendency to say one is better or one is worse and I really don't wish to do that here. I'm trying to give a pretty fair description of both watches from someone who is a fan of both Doxa and Rolex and I hope that people will read the review and gain an appreciation of both watches from it.

Before continuing with this review, I think it is time for a little history lesson. The Rolex GMT Master was originally designed in collaboration with Pan American World Airways for use by their long haul pilots who were traveling across multiple time zones. Pan Am asked Rolex in the 1950s to develop a watch which could tell different times simultaneously. The solution devised by Rolex was to incorporate a fourth hand which could be set to display a different time zone which corresponded with a 24 hour marking on the outer bezel. The GMT name referred to Greenwich Mean Time which was what pilots set as the second time zone. In 1972 the Aviation Industry replaced Greenwich Mean Time with Coordinated Universal Time (UTC), however, the term GMT is still used as part of the name of the GMT Master. Although initially designed as an aviation watch, today the GMT is popular with travelers and people who need to keep track of multiple time zones. The 1960’s brochure for the watch even included the following instructions for pilots on how to use the watch as an emergency compass. "In the Northern Hemisphere the Rolex GMT-Master may also be used as a compass. Simply point the hour hand towards the sun and automatically the red 24-hour hand will point to the North." In the Southern Hemisphere it will point to the South. Introduced in 1954, the design of the watch changed little over the years, with the exception of adding a Sapphire crystal and improvements in the movement. In 1981 The Rolex GMT Model 16750 added a quick set date feature. Previously in order to adjust the date, it was necessary to progress through all the dates in order to reach the desired one. The bezel insert comes in 3 flavours; red and blue (Pepsi) red and black (Coke) and plain black. Seeing the success of the Rolex GMT, other manufacturers added a GMT model to their line, the Doxa version appearing in 2006. In 2007 Rolex discontinued the "classic" GMT in favour of the larger GMT IIC. The C standing for Ceramic bezel. At present the bezel is only available in black due to an inability to manufacture a ceramic insert with an acceptable red pigment.

OK, so lets start with the one that started it all; the Rolex GMT. The version I have is the GMT Master II from 2002 (Ref. 16710). It has Solid End Links (SEL), holes in the case for the bracelet pins and uses a caliber 3185 movement. This automatic movement was introduced in 1988. It contains 31 jewels, oscillates at 28,800 beats per hour and has a power reserve of 50 hours. The bezel uses a 24-hour insert, which allows you to track time in two time zones and is split equally, red / blue, at the 6 and 18 markers. The dial uses Superluminova as luminous material. Originally Tritium was used, then Luminova and finally Superluminova from 2000 until 2007 when the model was discontinued. So if you are in the market for a Rolex GMT Master II, then unless you can find a NOS (New Old Stock) in an Authorised Dealer, you will be buying it second hand.

Doxa came late to the GMT party, but when they did, rather than design a new model from the ground up, they took their already successful SUB 750T design and modified it to utilize an ETA 2893-2. This is an automatic movement with hacking seconds, runs at 28,800 beats per hour and has 21 jewels. The bezel on the DOXA is the iconic NODECO bezel from the late 1960s, which gives you allowable bottom time for depth based on the US Navy Non Decompression Dive Tables. The SUB 750T GMT also uses a movable 24-hour chapter ring, which allows you to track a third time zone. Unusually the inner 24 hour bezel is split equally, blue / orange, at 5:30 and 17:30. There has never been any explanation as to why this setting was used. Personally I feel it unbalances the dial when the inner bezel is aligned at 12 / 24 hours. Full reviews of the SUB 750T and SUB 750T GMT can be found at www.doxa300t.com. The Doxa GMT comes in 4 models; Professional (orange dial), Sharkhunter (black dial), Caribbean (blue dial) and Divingstar (yellow dial).

Obviously both watches have GMT functions, which even though they have vastly different appearances, should make them pretty similar to operate. Right?...... Wrong!!! The differences between the functioning of the caliber 3185 and the ETA 2893-2 make for vastly different operations when setting the GMT hand.

Lets use the time in the above image as an example. Both watches show that it is just after 1 o'clock PM local time. How can you tell it is 1 o'clock PM and not AM? Well, you will just have to trust me on this one. I set the GMT hand to show local time in Ireland which is 6 hours ahead of the Central USA time zone. On the Doxa it is easy to see that the skeleton GMT hand points to the 19:00 hours marker on the dial which is 7 o'clock PM. The Rolex red GMT pointer hand is sitting at the dot between 18 and 20 on the bezel. Again this is 19:00 hours or 7 PM in Ireland. Obviously the minute hand will read the correct time in both time zones. This, of course, all depends on the bezel of the Rolex being set correctly to show 6 hours in advance. The Rolex bezel can be turned bi-directionally by hand. On the original GMT Master, you couldn't set the GMT hand independently. You rotated the bezel to a different time zone instead. The independently settable hand is the big reason for the "II" designation. On the Doxa there are 24 hour markers on the dial and the inner bezel. This means that 3 time zones can be tracked. One using the normal hands, one using the 24 hour marks on the dial and one using the 24 hours indications on the inner bezel. To set the inner bezel, the upper crown unscrews and turning the crown clockwise or anti-clockwise will rotate the 24 hour chapter ring either clockwise or anticlockwise. Since in this example the inner bezel aligns with the 24 hour indications on the dial, both watches show the same time, however, setting the same time is completely different using each watch.

Lets set the Doxa first. The GMT hand is set using the lower crown. It is unscrewed and a single pull engages the GMT hour and date function. Turning the crown clockwise will advance the GMT hand in 1 hour increments. The normal hour hand will remain on local time as the GMT hand is moved. The GMT hand can only be moved clockwise because turning the crown anticlockwise will advance the date. Another pull on the crown will engage the normal hour and minute hands. The second pull on the crown will also stop the second hand from moving. It is recommended not to change the date between 10 PM and 2 AM. During that period the pinions are being repositioned to carry out the automatic date change, any interference might damage the movement.

Now for the Rolex. This is where the movements differ. Unscrewing the crown and giving a single pull engages the normal hour hand. This can be rotated clockwise or anticlockwise . The GMT hand nor the minute hand is unaffected in this position. Another pull will engage the "normal" time setting of the minute and hour hands. As the time is advanced or retarded the GMT hand will move accordingly. I have to admit that since I have owned and wore the Doxa GMT for over a year before I got the Rolex, setting the GMT hand on the Rolex seemed completely strange and, as we say in Ireland, "arse about face". I think I've got used to it now, but I still prefer the ETA 2893-2 way of doing it. Apparently there are advantages and disadvantages to both ways. Personally I prefer to set the local time then set the GMT hand to the other time zone. It just seems easier with the Doxa.

Something that isn't immediately clear from looking at photos is that it is very noticeable when picking up both watches just how much bigger and heavier the Doxa is compared to the Rolex. The following table tells the tale of the tape. Weights are in grams, dimensions are in millimeters. The height of the GMT Master is to the top of the crystal. Add 1mm extra for the date magnification bubble. The weights displayed are for a 6 3/4" wrist and as can be seen the Doxa weighs in at 184 grams, whereas the Rolex is much lighter at 122 grams. A lot of this weight is made up by the bracelet. The Rolex bracelet has center links which are not solid whereas the Doxa is completely solid. The links on both bracelets are held together by screws.