What is the best Reel To Reel machine ever built?


Everyone who has listened to master tapes or dubs knows about the well balanced sound they provide. But it is also important to have a fine tape recorder or playing machine to enjoy the tapes' qualities in a good system.
Maybe my question was raised once before but the relevance of the topic is now greater as the tapes are back to more and more audiophile friends, especially those who are owning excellent phono chains.

I have seen many big & professional machines being recently offered and sold on e-bay, Audiogon and other platforms and I am discussing within a small group which machine is really the "holy grail" among the R2Rs. So why not here. I am interested in findings.
thuchan
wow, that would do the job, thats for sure.  If I could only come up with 30K, I could start my own business.lol
Albert Porter has the hots for a Studer 820. Another associate uses vintage Ampex decks.

Probably the best open reel deck ever built was custom made by an American, forgot his name. One unit only, I think. Pink Floyd's Gilmore said that compared to that machine any stock Studer sounded like a cassette deck.
But, I guess 2" Studer 820 should be exceedingly good to say the least.