GTR vs GTS, what's the difference?

I’d love to some day own an R34, recently my car broke down and I’m in need of another one. GTRs are out of the question as ones near me are over 10k, however there are some GTS’ in my area in my price range, equipped with turbo and goodies.

The only major difference I know of is the GTS is not AWD, are they worth investing in or should I simply save for a real GTR?