I would not really expect any of them to "mushroom", certainly not a non-hollowpoint bullet (and I don't know how reliable those would be). Your main goal should be penetration, which the heavier bullet is probably going to give you, even if it is going a tad slower. Then worry about the diameter of the bullet, and the size of the "wound channel". And since I don't think you're going to get any "mushrooming" with anything, it's best to start with the biggest, flattest point bullet you can get.