I know collision can be a very delicate part of game dev, and a poorly coded routine can ruin a very good game otherwise. I asked not because I doubt of your skills but because I don't know yet how to handle that on the Prime myself. I don't need it for Trailblazer (which is really almost finished, I coded track editor on-calc in the train, that was an... interesting experience. ^^ ), but I will definitely need some for my next project. There are so much known way to handle collision but each platform has its own strength and weakness. Well I hope it will work for you and I really look forward to play your game. Will you release a demo soon ?
Indeed collision detection is what I dread implementing the most because I always wonder if my initial ideas will be fast enough (and more often than not, they are not fast enough). Speed is not only a result of good ideas, but also of good data formats. Unfortunately, I tend to figure things out by trial and error rather than spend a lot of time planning out the code.
As for a demo, I will probably release one after I at least implement one enemy type and make it destructible. In terms of ease, a simple enemy type would result in a faster release of a demo, but I think I may go the longer route and program a mini-boss for a demo.