I own a Viva Solista and it spits out a fair amount of heat but I have a basement listening room and so I don't mind. It does not generate nearly the heat of an OTL though. I have had a set of Atmas in my room and I enjoyed them although the speaker was 4 ohm and thus not ideal. I found them (MA-1s I think) to be clean, fast and wide open. Very good. I always wanted to hear or own the Joule Electras as well. I almost sprung for a pair of used Rites of Passage, and those would have turned my listening room into a sweat lodge with mystic visions abounding....