Boa2, in response to your question, amps designed for Class A operation all run hot, whether OTL or not, whether tube or solid state. It's the Class A operation, not the fact that they are OTLs, that results in the heat. The best of the OTL amps (Atma-Sphere, Joule, Tenor) are run in Class A for best sound. For a while, Atma-Sphere made the MA-1 and MA-2 models with an optional switch to change operation from Class A to Class A/B to address the heat issue, but I think Ralph dropped that as a standard feature because most owners never wanted to make the sonic trade-off and left the amps set for Class A anyway.
[D]o the OTL's and their little tube armies run especially hot?