JDoyle
I am very happy with my B&K 7270 amp. I have tried the experiment of running two 626R's as a center using a bi-wire speaker cable from one channel only. That means the amp is seeing a 2 ohm load, in theory. The amp is rated and tested at 8 and 4 ohms, according to the manufacturer, and also is stable to 2 ohms. I did not seem to have any problem running both speakers from one channel. I have, however, just to be on the safe side, gone to running each of the two center 626's from a separate channel, spliting the signal coming from my preamp center channel. I really cannot hear a difference between them on one or two channels.
I have run both dynamic and hybrid ribbon/dynamic drivers speakers with the amp and it does an excellent job.