Raystorm HD.
Was torn between that, Raiden IV, Raiden Fighters Aces, and Rez HD.
No regrets, the game's awesome. Got torn up by the review sites like Gamespot/IGN way more then it deserved, with an odd complaint about a 15 dollar price tag being too much.
Lets see, Raiden IV is a 20 dollar digital download, and it used to be 40! Ikaruga has always been 15, Raiden Fighters Aces is 20, most Cave games like Deathsmiles are around 15-20, and this one package that includes Eschatos and Judgement Sword is nearly 60!
So where are all these shmups on Xbox Live Arcade that are better then Raystorm, and far less expensive?
Best I could figure, the reviewers either have a personal bias against the thing (They often talk up Ikaruga in the process), or they assume Raystorm just doesn't have the cult following of a lot of other shmups, and so show their true colors against the entire genre when they feel there's no one to cater to and draw in those clicks..