The nifty case is 55mm but is also 84hp so a bit bigger, although that could be seen as a plus. I don't have any experience with these cases but seems to be a decent bargain with the included midi.
-- mog00

I started with a NiftyCase! I think they're great! If you're considering getting one, I would recommend doing so. But they don't offer the portability of 40HP, which was an important consideration for this system.