Amp recommendation for B&W 801 Matrix SII speakers


I recently acquired a set of B&W 801 Matrix SII speakers. I am looking to acquire both an amp and a preamp to match up with the B&Ws. These speakers are very inefficient so I need something with lots of power. I am guessing 350 watts at least. I have really got power amp on my mind first with a budget of $5000-$10000 or thereabouts. I want something new or no more than a couple of years old.

I currently have a MAC pre C2300, MC275 amp and Klipschorn speakers. This is a system that I really like but I am thinking with the B&Ws I probably will want to go SS state on the power amp. The MC275 is not a good match for the B&Ws. Needing a lot of watts probably takes me out of tube territory. I am not an audiophile so i really don't know what all is out there.

Some amps that interest me are:

Pass Labs X350.8 $13500
Pass Labs X250.8 $9600
Mcintosh MC452 $7500

Thanks for the help....
wemfan
Effischer, I am really surprised that you liked the MC302 better than the 452. I thought the 302 was Mac's entry level amp and not quite up to the quality of the rest of the line of current Mac amps.

i have heard some about Rowland amps. I will check them out.
MC302 is a newer design than the 452. They changed something and it definitely improved the sound, IMO. That's the fun of the hobby - finding the pleasant surprise!
Just did a double-check on Audio Classics' site and realized I made a mistake - had auditioned a 402, not a 452. Not sure how much difference it really made; the 452 is really only an update of 402. So many variables when doing demos, anyway. Still wouldn't trade my 302 - it works wonderfully in my room with my speakers. Price does not equal quality and is never the bottom line.

BTW, I believe the 801 Series II are some of the finest speakers ever made by anyone. I'm way jealous!
I have liked all of the Mac amps I have heard. I am sure the 302 is a good one. I really like my MC275 but I think these B&W speakers are going to preform better with a solid state amp. I do appreciate all of the suggestions so far.