I used several amps on Martin Logan Monolith IIIs in a 25X23X10.5 avg listening room with no power issues. Audio Research Classic 60, Counterpoint 400, Bryston 4B. However, my new wife had great issues with the terrible sound for rock, no bass, head in a vise dispersion for highs, lack of dynamic contrasts among others I forgot. Dumped them for a pair of Legacy Focus and Signature IIIs (kept the latter). We were happy for decades.
Electrostatics and tubes
I am looking to get some new to me speakers, I've been looking at options and would really like to try a set of planars "electrostatics". I have read or heard somewhere that as far as speakers go they tend to be inefficient (85 to 89) vs.90+(db) on the Klipsch or Dali's I've been tossing around as a standard speaker option. I guess my question is would I need to worry about any over heating issues. I plan on using plenty of power with a set of VTA, M-125's to power them. I am looking at a lower budget set maybe Martin Logan ESL 9's or Magnepan 2.7i . Just wondering I would hate to over heat a few hundred dollars worth of tubes if I don't need to. ¯\_(ツ)_/¯ don't roast me to bad I cry easy 
thanks.