I'm not sure I'd trust the cover's grip to safely hold the 360 in place indefinitely. Not if you're going to be flipping it around regularly; it's just a hard plastic friction grip.
Why not just use industrial strength velcro along the 360's rear "slot"?
That's how I hold my (much heavier) IQ in place. And it's both cheap and readily available. I use two strips for the IQ, so one should suffice for the 360.