Valve or SS ones? Never dealt with the SS stuff, but the valve stuff has a big giant flaw in that you can't adjust the bias without modifying and losing the warranty, and that sucks really badly, and their use of racist stereotyping to try and justify it in the manuals really doesn't help.
[quote]Visualize, if you will, a group of sub-atomic Irishmen milling about and in a repellent, negative state of mind. All are scowling and none wants to have anything to do with the other. Now introduce a strong attraction say, a public bar, and you can easily picture an orderly, if rapid movement of the lot in a single direction. This is what happens when a positively charged element called the anode or plate is introduced into the vacuum.[/quote]
The fiddlier amps are badly designed from a service perspective also. Harder to go wrong on the simpler stuff since its all on PCB for ease of mass production, price doesn't reflect that though.