Some sims have changed to 64bit games probably to take advantage of more memory usage and other things I presume, why is it that RRE is still in 32 bit? If 64bit is available is there a way to make sure RRE runs it? Or won't it improve anything where performance is concerned?
I depends if ram usage is an issue for the game. really poorly optimized 32bit games like minecraft needed a 64bit version because they would just use all the ram they could and crash. Im sure sector 3 would upgrade if ram was an issue but unless your randomly crashing do to using too much ram there is very few other advantages. theoretically if you can load all the necessary information into the ram and graphics memory you can use more cpu for the physics calculations ect... so it depends were the bottle neck is it could be ram in which case a 64 bit would help. but if it is the cpu compasity or speed, graphics memory or ram speed 64 bit probably wont help much. all this is really what makes game optimization so difficult. some one on a low end machine might have a different bottle neck then some one on a gaming pc so being able to account for all these things is the key to good engine design and is why consoles are so popular.
In my opinion, 64bit is the way to go with a long-term perspective. It gives more posibility to the developers. I bet devs are already aware of this. But I'm worried about GMotor2 engine. If it does not designed for x64, they should port entire source code manually. This is very risky and needs more man power. ( e.g. QA is doubled. ) Even worse if they don't have the full source code, they can't. Hopefully not.
A small downside to 64-bit is that memory pointers are twice as big now, which means some data structures may grow and use more memory and have worse effects on cacheline utilization (though avoidable by pointer-less approaches). Though as @taxfree said ultimately you'd want to have easy usage of more RAM as people have more RAM these days (although it's more relevant to games with lots of dynamic entities)... looking at the steam hw survey, however, the fraction of systems <= 4 GB is still 45%... and VRAM is also <= 1 GB for a lot people still... http://store.steampowered.com/hwsurvey