Goddamn this game is addicting. The lack of a campaign kind of sucks but I like shooters and played the timed modes a lot in the older SS games so I figured I could get $8 worth of enjoyment towards it. I've definitely enjoyed the hell out of it so far. This game is really beautiful and plays so well...it's a really fantastic shooter. The interface is really slick, the controls are perfect, everything about this game is great except for the lack of modes. But whatever, when you try to download the game it tells you outright that this is just a timed score attack, so you know what you're getting into.
I've been playing for quite awhile, and it's awesome if you're into score attacks like this. It's extremely satisfying to score slightly higher on a run and see your place on the leaderboards jump up a bit. I've played all the 360 shooters and although the rankings are fine on that, I really like how SSR is just made to be a score attacker. It's short and to the point with a lot of stuff to combo off of and lots of hidden bonuses that you can take advantage of.
Right now, I'm ranked #9 in the Northeastern USA 2 minute mode, and I know that I can keep improving on it. I haven't really even done much with 5 minute mode yet, I should probably work on that. Definitely worth the $$$ if you're into this sort of stuff, but don't expect anything resembling a normal shooting experience.