The GSR has longer gears, so in theory, it's faster top-end. There isn't a governer, it's drag limited (not enough power to fight the wind). The Type-R has more power, so I'd assume it would get closer to top end.

Really though, I took my Type R to 142 indicated on the highway once. No one needs to go that fast.

94-95 had an older diagnostics system (OBD-I) that responds pretty well to mods. If you're getting a GSR, those are the years to get.

They only brought the Type R over in 97,98,00,01. You'll be paying a premium for it, so if you aren't willing to plunk it down, just get the GSR.