I have been running them with a Stax SRD7-pro since I bought them in May; the integrated speaker amp is a push pull pentode amp. I've been enjoying the sound very much, though I am upgrading to a dedicated amp. But I'm not in any hurry to do so.
YMMV I usually do these hifi purchases spaced far apart, unless something is really lacking. But so far my impressions are the same as the first day I heard them, I look forward to listening to the setup every evening