I have a few comments for you. None of these are really dress watches that can be work with a tux. Ok the Bond did it with a submariner... The milgauss is a dressy casual watch, and IMHO is only worth it with the green dial and that is going to stand out, and not in a good way for a wedding. Good luck finding a Spectre 300m they are pretty much sold out and afiak Omega USA boutiques have zero left, some authorized dealers may have them, and rumors are some are still available in the Asian boutiques. The blue aqua terra is like the milguass a dressy casual watch.
All of these can be worn with suits in most situations, and hell all of them can be worn with a tux, although the 300m is going to sit high and may have an issue with your cuffs.
What I would do is buy the watch that speaks to you the most, which will you get the most use out of? Which will you wear the most after the wedding? What do you do for work, and for fun?
Omega and Rolex equal in quality for the most part, Rolex has slightly better materials, Omega has the better movements. That being said the higher price of the Rolex is more due to marketing and its affect on the market and future resale, oddly this does not mean the Rolex is over priced. That being said the material of the hands is not an issue and honestly I've never heard it come up before outside of Rolex marketing, the gold/silver value on hands would be negligible when factored into final costs, think about it they are a tiny fraction of the weight of a weddingband and a plain 18k wedding band is not very expensive.
Notes on each
Submariner - Classic iconic watch, tends to stay very stable in value as Rolex tends to raise prices every year which keeps the used/vintage market high. On the other hand it is a Submariner which everyone and their cousin has. Everyone will notice it, can be worn with everything even a tux according to James Bond. Watch guys have huge mixed feelings on this watch, on one hand it is a iconic classic design, on the other hand its the watch that everyone that wants a nice watch gets.
300M Spectre - drop dead looking watch, and the 300m its based on is the exact same look from more then 3 feet. I am currently kicking myself for not getting one. This is a vintage inspired tool watch, and should hold value decently well, although this one might go up.
The Milguass is a like an engineers watch and at this point slightly archaic. All of the "master professional" Omegas are leaps and bounds more anti-magnetic at this point and do not actively advertise it. The milguass is striking with the green glass, but its an engineers watch in my mind and not sure about how others feel, but it is not really an active sports style watch. Last I checked they hold value pretty well.
The AT 150 is a dressy causal watch like the milguass but is more of an active sport watch at least in my mind, and will wear alot bigger then the milguass on your wrist. This is a watch you can take to the beach or the pool then slip on a suit and go out without ever taking it off, like the Sub, but it is a tad more fancy with the dial work. This watch tends to lose more on the used market then the others.
At the end of the day it is up to you and your budget, try them on as they will all look different and wear different on your wrist. You might be surprised that 1 or 3 of them just do not look right when you wear them.
