I own a Technics RS-1500 and an Otari 4 track MX 5050 that comes in two pieces. Since I've owned a number of reel to reel decks, I see things a lot of people don't see; like tape handling for example; the more expensive Otari is a beauty to behold, the tape moves silently without a sound as do all of the most expensive decks, but it's extremely complex because it's a "professional" machine.
The Technics is reliable and easy to work on, I replaced all the capacitors in mine with "Black Gates", and I also replaced all of the transistors; quite naturally I get superior audio.
Since the Otari is "quarter track" and the Technics is half track, comparing the two is like comparing apples and oranges; the half track naturally sounds superior.
I don't care what brand I got, I wouldn't want anything less than a half track.
In regard to your question, although I've never owned a Studer, from what I know, that's the one to get, but I'm more than satisfied with my Technics.