I own a XA100.5 with WP Sasha. Before buying tha XA100.5, I compared it with a XA60.5 that is a very great amp. The difference between both is the bass are far better articulate,with XA100.5. I compared the XA100.5 with the X350.5, and I prefered the XA60 because it's much more musical, you feel more involved into the music. So if you do not need the power of the XA100, go to XA60.5.
^jp
^jp