If you want a really cool amiga system, which is for classic games and demos, go for an a1200 with a 68030 accelerator card. (With a few MB of fastmem of course.)
This is compatible enough for games and demos, and have the speed too. Get a decent hdd too, loading games from it really faster than from floppies. And if some games isn't compatible with your new system, then you have the option to run WHDload. It hase the remedy, nearly all games and demos. And the whole thing will be not too expensive.
