These things do seem to run HOT. I saw a 3-series at a big box store, and I could not keep my hand on the top cover. Maybe it sounds tubey because the parts in it glow like tubes! 
I used to turn a blind eye to the issue of heat. At the time, sound quality was paramount over all else to me and I could put up with my SE amps pumping out a ton of heat.
Maybe it was because of the simple topology of these SE amps that I didn't worry about one of these amps pooping out from heat related stress - it was easy enough to track down the problem and fix it.
But with these all-in-one JVC wonders, how are you going to fix it if it poops out and you've got no warranty? It gives me the willies!
Luckily they're comparatively affordable, but what a PIA - and it' still a good chunk of cash.
All other things being equal, it seems like the Sharp EX-111 or one of the little Tripath amps would be so much more reliable in the long run simply because they don't have the hot-running hybrid technology JVC's been using since the F10 (the original ES1SL runs much cooler).
Do the new JVCs sound better, though? Who knows? Doesn't look like anyone's done a comparison.
Best,
KT
