Gee, if we only could demo everything. Jrud, did you digest the nine reviews each at audioreview for the Classe 301 and Pass 350? They are very instructional. All the Classe reviews, both negative and positive, are perfunctory at best, while all the Pass owners wax eloquently over their amp.
I am prejudiced, like all the other Pass Labs amp owners. I loved all aspects of my X-150 so much that I went out, and without flinching, shelled out the bucks for the X-600 to power my new speakers.
There is a technically compelling reason to believe in the superiority of Pass. I have a good friend who builds great amps. He studiously follows all fellow amp design accomplishments. According to him, the Pass X and XA circuits are ahead of all the competition. With some research, this becomes obvious to all but the most entrenched.
To make it simple as I can, what Nelson Pass did was to create an amp using no general feedback, while diminishing distortion a hundred fold. Because the signal is unfettered by nary as much as one capacitor nor resistor, full dynamic range is preserved, and that makes this amp BIG. The free signal also amplifies every facet and every nuance.
It's one great looking amp too.
Oops, its the 250 you are looking at. No matter, all the X amps enjoy much the same circuitry.