You'll get a lot of advice on these speakers, but one thing that really worked for me was to pair them with a fast subwoofer, in my case a Martin Logan Depth. The La Scalas sounded excellent, but really didn't become special until paired with a quick sub.
I've gone the high-power SS (CJ Sonographe 400), high-power tube (Rogue M120), and low-power tube (Quicksilver Horn Mono) routes. Low-power tube + fast sub has been by far the best combo, hands-down. Purists would note the Quicksilver horn monos are "mid power" (~25w), but the point remains that you don't need much power to drive La Scalas, and in my experience, less has been more with these sensitive speakers.