The Pass Labs products are very good, I might suggest going a generation older to the Aleph series when they used a single gain stage. They were not as powerful, but they sure sounded good. Aragon 8008st or 8008bb are both good options too for an inexpensive but powerful amp. It would suck to have to buy just based on a few opinions here, from people you don't even know. Ideally you NEED to listen to the amp in your system, but when you buy used, if you don't like it, sell it and buy another...