Since I own 3 different Pass Lab amps, the XA-30.8, XA-60.8, and X-260.8, as well as Sound Lab U-1PX, and U-545PX, I can definitely state that more power would give you more satisfaction. While I have heard Sound Labs driven by Atmosphere amps on many occasions, and can attest they do a great job, I have never desired to own them. I am extremely pleased with the results of my Sound Labs being driven with Pass Lab amplifiers. In my opinion, the biggest Pass Lab XA series amp you can afford will probably be the best, assuming it’s big enough. The XA-30.5 or .8 does not have adequate power in my experience. If you can’t afford sufficient pure Class A power, the X-260.8 is a good compromise, and will drive even the least efficient Sound Labs well. Of course, room size is always a factor.