sonus faber strad power amp suggestions


I am powering sonus faber strads and martin logan summits and anML center channel through a krellkav500 and akrell
foundation preamp I should put the strads thru a separate 2channel amp ,suggestions bryston4b3 or passlabsxa350.8?
drmarshotel
I am using Pass X260.8 amps with my Strads and really enjoy the combination.  They have more than enough power to fully load my 17 X 34 X 9 room.  They stay in Class A up to 34 wpc, which means that I'm listening in Class A most of the time.  The amps are detailed, dynamic, and on the warmish side.  I use a Pass Labs X22 preamp and X17 phono.  In my experience, whenever I use electronics from the same manufacturer there is a special synergy.   While there are many good options, Pass Labs is hard to beat for the money. 
i could spend on the high side of $5000 for the right piece,I imagine a 5-channel preamp upgrade would be additional. I am leaning toward Pass Labs ,is 150.8 enough...or 350.8? I listen mainly to dvd-a and blu-ray formats(steve wilson prog rock remixes, highly detailed stuff). so $10k+ for the two pieces should be doable