I own an Onkyo (TX-DS797 - basically the same as a 701) and am completely satisfied with it's performance. I've never heard a Denon, but from everything I've read here, and elsewhere, they are excellent receivers. The fact is, you can't miss with any of the 4 receivers you mentioned. Find the one that has the features you like, and go with it. All 4 should work well with the 22s.

Jack

"People generally quarrel because they cannot argue." - G. K. Chesterton