Diebenkorn
I've successfully used my 100s with the 70ish watt Prima Luna monos, but prefer my ARC VT130SE which is app 120 watts per. My room is large (app 23' X 14' X 17' ceilings, with a large open space behind the listening position) and I do go pretty loud on occasion. OTOH, I use subs which reduce the main amp's workload. Overall, I'd say 100+ watts is a good idea, but you can certainly get by with less in most rooms.
Marty