The quality isn't better but you can give the appearance of high detail. Good antialiasing is the key my friend
When the ships flying by you at speed you just pick out shapes, that's what I concentrate on when I'm designing texs. The finer detail looks nice in the loadout screen and tech room but when it really matters i.e. ingame you don't make out half of the detail, in which case it's a little silly putting a large high detail texture on a ship.
Look at how good a job [V] did with 256*256 texs, those models look excellent in the loadout screen and ingame. I think 512*512 is probably too large, textures have a big influence on how fast the engine runs so a smaller tex has better performance in it's favor.
I'd like to point out though that a lot of ppl get excellent results from using larger texs but it makes sense to balance it out, I mean you won't be able to make out the carefully detailed pilots name under the cockpit window when your dodging enemy fire and attempting to off the bugger
