The new Cayin integrateds are very nice. The KT88 version with 4 tubes per side is one awesome amp at a great price. Swap in the new Genelec KT88s after the stockers wear out and you will be sittin pretty if you can do with the moderate power - 100w maybe?
All tubes is what I prefer, the goodness of a tube pre amped up even more. But I keep looking for a SS amp that can do as well to get rid of the tube negatives. High price, reliability, heat, maintenance, size, lower power/price ratio than SS. The output impedence (in the best cases) is not as low as SS (.01 ohms typical) , and in the worst cases is downright abyssmal, like 3 ohms or even higher. Look for an honest output impedance rating of <1ohm maximum. The lower the output impedance, the better the amp will perform overall into speakers loads withfrequency dependent impedent variations.
http://www.transcendentsound.com/amplifier_output_impedance.htmTo me the headaches and expense of an all tube rig are worth it. I could spew a mouthful of hifi codewords to describe why I like them, but it would mean nothing to you. You just have to hear a good tube system with low distortion, high power tube amps playing through full range low distortion speakers. It will ruin you!
If you have a hifi dealer near you that sells VTL or Audio Research, try to go there to hear what it's all about. No guarantees that it will sound good, most dealers can't set up a system properly, but you might get lucky. If not look for a tube audiophile nearby and spend some time with him. We are all nuts and love to share the insanity, so you will get an earful.
If you keep some extra parts on hand like tubes and fuses you can usually fix any of the routine annoyances yourself. A good brand will have less annoyances than others. It is best to hear a great tube system first, try to fall in love with tubes before spending money on them. You will need the lust factor already built up high enough to help you coast through the learning frustration when it doesn't behave like a denon receiver.
Rich