I can only comment on the 7250. I've had it for about two years now and am extremely happy with it! It's a great amp for the money. B&K are very supportive when and if there is a problem, I have no problem recommending it! Good luck
I'll have to disagree with the others. I think the 755 is the better amp (actually a ATI with a different face plate).
Just about all the power one could need, great quality, great price, great warranty.
It is not a warm or cold amp, but just very nuetural, which is how I like it. What ever you put in is what your going to get out. So, if your looking for an amp to add some characteristic to your system this may not be the amp for you, but if accuracy and detail is what your after, this one will fit nicely.