I would say to keep things inexpensive and pick up a used Hafler 9500 or even maybe a 9505. I bought the 9500 new some time ago and sold it to move up to a Krell 300c. I wish sometimes that I would have kept that amp! It was a super sweet sounding amp! Don't get me wrong, the Krell is also a nice amp but I don't think it does as well with electorstatics as the Hafler amp did.
I have not heard the Spectron but have heard the other 3. The Berning is going to be tough to find used and is no longer available new from what I have heard. The Moscode is a great amp. I believe the new model 402 is being debuted at RMAF this month. I'm confused as to whether it will replace the 401 or be available in addition to the 401. Price tag on the 402 is about $6500, but Moscode allows for 33 day in home trial period. After I hear the 402 next week I may bring it in for a listen. I've always liked the Moscode design.
Of course you've read my opinions on the D-225. Bottom line though is these are 3 great options. I don't think you could make a bad choice.
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