I had a pair of QuickSilver M135 monoblock tube amps for 24 years. No repairs other than 4 full sets of tubes (& a few fuses blown by over exuberance or an EL34 tube failure).
I bought a pair of McIntosh MC501 monoblocks, and on the same speakers side by side it was VERY hard to tell the MC501's (SS) from the M135's (tube). I really think its those crazy output transformers in the McIntosh. Only other SS amps I've liked Bryston 28B monoblocks. (I've heard several other Bryston amps, but they sounded terrible!)
Now, the MC501's were bought used from a dealer who bought them back from his customer who bought them to replace his VTL tube mono's. After 6 months he wanted his tubes back.
I bought a pair of McIntosh MC501 monoblocks, and on the same speakers side by side it was VERY hard to tell the MC501's (SS) from the M135's (tube). I really think its those crazy output transformers in the McIntosh. Only other SS amps I've liked Bryston 28B monoblocks. (I've heard several other Bryston amps, but they sounded terrible!)
Now, the MC501's were bought used from a dealer who bought them back from his customer who bought them to replace his VTL tube mono's. After 6 months he wanted his tubes back.