Hello, Bruce.
I've got a Synergy 240/3 that has been used to drive PSB Synchrony 2, Paradigm Studio 20, Proac Response D2, Meniscus Adelphos, Harbeth 30.1, and GR Research OB design speakers, but no Electrostats. I have never felt my amp ran hot. Warm? Certainly, but never hot.
If I had Maggies or other electrostats and wanted to power them with an AVA SS amp, I'd want Frank's Synergy 450.
Just my opinion. YMMV.
Michael