What are the weak points of Pass amps and pre-amps ?

None of the Pass products (including the classic Nelson Pass stuff) are engaging IMHO....

... from sound perspective

... and from my bullying friend's perspective (he keep bragging and preaching about his Pass)

Don't get me wrong.   They are fine products by any standard.  But just don't engage me at any level.   Almost like Boulder.  I feel like I am listening to an top notch electronic lab instrument.

Alright, I think I get the picture.
bsimpson, I especially thank you. You confirmed my impression that was formed after reading all the posts and a few other threads and reviews.
Sound, whatever else it should be, must be engaging. Just like people, I could add.
So, practically speaking, it appears that I have no need for Pass.
From what I gather, brands like Gryphon and Ypsilon are not just better, not in another league, but in another universe. And that is worth paying for.

Hi inna, I have been considering purchasing a pass amp, so I have been following this thread. You inquired regarding the weak points of pass amps, and just guessing you received about 99 responses praising their sound, and two or three not positive responses. I thought the responses were overwhelming favorable, do you mind mentioning what lead you to think otherwise? Thanks

I have extensive listening to a high end Ypsilon preamp a new friend's home.  That and High Fidelity cables had me run from his listening room the first time.  After replacing the horrible cables, the preamp was the next culprit of an $850,000 system in producing bad sound.  It was replaced by a VIva pre-amp.  I doubt Pass pre-amps could sound as bad as an Ypsilon.