Are Pass Labs amps probably the best ever you can buy ?

No other company I know of takes care of their customers like Pass Labs. You can call them at any time and discuss your entire system. They will cheerfully talk to you. When it comes to repairing something NOBODY compares to Pass! Their philosophy is not to charge for repairs more then
necessary. I had a Pass Labs X1 preamp for years. It finally needed work. It was of a vintage that they needed to replace several circuit boards in order to facilitate the repair. I braced myself for the bill. Including a new shipping carton they charged me $125.00!!!!! Insane but great for me and all who decide to be Pass owners. Good luck. Joe    

I have owned many of the Pass products There is no better SS amp
made anywhere. And the customer service is second to none. You will not be disappointed. 

It all comes down to system synergy and with the right front end and the right speakers, Pass Labs are extraordinary. I have heard Pass Labs sound only so-so, but it has pretty much always been due to poor speaker synergy.

For my Audio Physic Avanti III, the Pass Labs XA60.5 has really turned out to be the best.

Pass labs would mate best with 93+dB sensitive speakers, imo. Unless you get one of the 100w class a ones but I think those are well above $15k mark!

"At Pass we build amplifiers with excessive output stages, huge heat sinks and massive power supplies. We use the highest quality components in simple linear topologies, assembled and tested with great care in Auburn, California. They measure well and sound great. They are heavy, reliable and expensive."
In my opinion, the only way to go is class A and I'm not sure anybody does it as well as Nelson Pass. Beyond that, Nelson is just an excellent human being that embraces a great life philosophy. I think the thing that makes Nelson such a great guy and engineer is that he finds fulfillment and joy in giving and humbly receives new ideas and approaches to things through that process of giving and interacting with his customers, fans, and DIY'ers. That guy has taught me a lot. His followers have taught me a lot. 
Best amps there are? Tough question. Are his mainstream amps everyone's cup of tea? No. The guy readily admits that some speakers pose problems for amps that he doesn't waste time worrying about. On the other hand, he's designed some amps that are ideal for very unusual speakers. They're all very well built. He puts a very high priority on his designs being very stable and reliable. I love my F5. I haven't heard anything yet that compares to it and there's definitely room for improvement. But I'm sure it's not for everyone.