I use all three makes of camera mentioned, with slight model variants. I would summarize as follows:
Rolleiflex T....My favourite. Utterly reliable, had mine since 1978. Not once has it needed to see the inside of a camera repair shop. Tessar lens excellent, particularly for black & white. Slightly on the "cool" side with colour, so a skylight filter recommended in most situations.
Yashics 124. ....As has already been mentioned, less plastic parts than the 124G model, so probably a better buy if you can find one. Built in meter accurate, but it is geared for the older mercury battery type, so an adapter need for silver oxide replacement, not a major problem. Lens quality excellent, slightly less contrast the the Rollei. Comments have been made re. the 124G being more fragile than the Rollei, but my 124 has been fine, and should last for years if you don't "hammer" it. Focussing screen not as positive as the Rollei.
Minolta Autocord.....Lenses give superb quality, as good as the Rollei in my opinion. It's a very "quirky" camera. The film loads in the opposite direction to other TLR's, making it awkward to reload while on the move. The unusual focussing lever takes some getting used to. Definitely a camera for slow, methodical photographers, not for those in a hurry.
Summing up.....The Rollei T, would be my first choice, but these are getting difficult to find in really good condition, and when they are, they're very expensive. The Yashica 124 or 124G would offer the best value for money, and there's more of them around. The Autocord is more difficult to find since they were discontinued earlier, and offers more of a challenge to the photographer due to their quirky operation, but if you can get used to it, it's an excellent camera.