I bought the 4A SE ultra with all the upgrades the good doctor had to order (about 6 months ago). I must say its a sleeper that can be upgraded to run with the big boys. I highly recommend the Revelation Audio umbilical cord as a worthwhile upgrade (although the guys at Revelation can be a bit slow to respond). Also try some NOS stock tubes (I forget which ones but I can look it up for you if need be I picked them up after reading a recommendation from another MAD owner)
My Ultra 4A SE feeds into a solid state McIntosh amp (MC402) driving Dynaudio Special 25s. Its a very sweet setup.
The MapleTree preamps are an excellent value for the money.
Good luck
Tony