My PSB's are also low ohm and my Denon 3300 does get hot. I used to have it in a closed cabinet and had to add a cooling fan to keep it cool. Now it is open air, so no issues, but better start looking for a fan if you want to protect your AVR from heat and little fingers. And yes, little fingers can F up a Denon AVR - been there, done that.

Panny 3000 PJ, 118" Carada, Denon 3300, PS3, Axiom QS8, PSB 5T, B&W sub, levitating speaker wire