1. GMT is for if you travel a lot or you knowing someone important is outside the state, really need that two time zone. If you just sitting in office, face the computer then you don't need date. You can see it on your screen. Also don't have to worry about the date change issue. Tudor GMT can't never beat Rolex GMT. Also I'm not a Pepsi fan. lol 2. The chrono, I have 116503, you will not use chrono a lot, the sub bezel will be more easier and more often to use. There is no road for you to speed that fast unless you go on track. 3. and 4. If you have big wrist, very high recommend, nice and big with date, also come with rubber band for you to change and wear. The sub bezel is easy for you to time. If you have small wrist, then will be no, cause will be chunky on your hand. I have a black bay and I have small wrist and is very big on my wrist, feel a little be bulky already. 5. The one I purchased, I'm very happy about this one. I was consider why not just get Sub or BB58. For daily use, 70 hours power reserve, and don't wanna worry scratches on a Rolex will hurt your heart, then black bay might be a good choice. Between Black Bay and BB58, like I said, I have 116503, so I don't wanna another watch have feel same type of gold color on it, BB58 use rose gold on bezel, but still type of gold color. That's why I end up with black bay.
Hope those reasons can help you to pick your watch.