Amp for Sonus Faber Cremoma M

I am looking to upgrade my amp for the mains to improve my 2 channel sound. I currently have an Emotiva XPA5 that I will continue to use for the center and rears when listening to concert DVD's or Sacd's

I am considering Emotiva XPA1 Mono Blocks @ 500 per channel / 1000 into 4 ohms for $2000.

Would I get better sound buying a higher end amp used,for example a Pass Labs x250.5, McIntosh MC205 or Krell Kav3250 which would also run my center for SACD's?

I appreciate the input as I have found that it is very difficult to demo amps side by side with the same speakers / electronics.