Hmm, I have the 390 boss and ended up using the zero cant beds. (I actually discovered this after I forget the beds and spent a day riding with nothing - direct onto the disc. And unexpectedly that felt great! So I put in the zeros when I got down the mountain and haven't looked back since)
But i'm going to try the cant ones this season to check I really do prefer it that way. I'll know by Dec 15 if i'm willing to sell...