Okay, ignoring the fact that the GO is about two thousand less than the Globemaster, which is the better choice for a lifetime companion?
I'd go with the GO. I like the larger date and I've never been a fan of Steel watches with a yellow or rose gold bezel and don't get me started about that two tone bracelet. Just screams, "Wannabe" to me.
I think the GO is a more interesting elegant watch, but I am not a huge fan of Roman numerals for this version. I agree with @oddboy that a blue dial SS Globemaster on a bracelet + leather strap would be a more versatile option. It really depends on what you have in your collection and how you plan to evolve your collection. If you are going to have a sports watch down the road the GO might make more sense as your formal wear watch.
Of those two I'd go with the GO. Pure class. If you were comparing it with an all SS Globemaster, it'd be a tougher call.
I vote GO but right now I am biased. I just received the GO Senator Excellence last Friday. I also am not a fan of the 2 tone on the Globemaster.
This GO seems overgrown dress watch. Globemaster is suitable for dress and casual wearing. Service will be easier with Omega.
Thanks for all the comments! I've always liked two tone watches and other than my wedding ring, have never owned anything gold. And as Dolly Parton said: "It costs a lot of money to look this cheap." But that GO is really something too. I'm going to have to phone or get out of the booth soon. Thanks again.
Looking at the GO you chose it appears to be in the same case as mine. Of course you should try it on but I think you will like it. It sits very nicely on my wrist, its not overly thick and is a great diameter for most people. Craftsmanship is awesome, overall a very fine watch. I like the GM and it is in the top 3 of my favorite Omega's but I like the GO just a bit better. I had all of these on my wrist less than a month ago and the GO is the one that called to me most, of the ones I could afford .
I wear my watch for everything, so I need durability, and the Globemaster is probably my favorite current (non-Moonwatch) Omega, so I'd go that route (but in steel.)