While I myself have a Technics 1500 rebuilt by Jeff Jacobs at J-Corder and modified by Doc B at Bottlehead into the King/Cello pre-amp, I have heard Greg's UHA decks a number of times a number of times, and they are stupid good. Absolutely beautiful playback. Are they the "best"?
I can't say they are and I can't say they are not. With the huge uptick in Reel to Reel in the high-end community there are some mighty fine machines to be had, including the afore mentioned UHA, the Studer family, and for the gonzo among us, a tricked out ATR 102.
That said, my modest 1500/King Cello setup gives my Walker TT a run for it's money in analog reproduction.
The UHA decks are real eye candy to see as well. They are completely reworked and my 2 cents worth says they sound great and are worth the money. YMMV...