it may not be awfully rare, especially when compared to some of those big saturn games, but it does rock. there's a pretty neat transparancy effect in the bonus levels that isn't in the (generally superior) jaguar version and it features CD audio. Quite the bargain considering the only reason most people buy the jagCD is to get a CD copy of that soundtrack. did all saturn games come with a foam block, or just some?
no, tempest2000 isn't really rare on any system
now tempest3000 might be somewhat rare.