As I've been following this lengthy thread since day 1, I wanted to share two divers' subjective assessments after 40 dives with the TFX (unadjusted from factory tuning). For reference, our previous second stages were lightly-tuned Atomic ST1, but we've also used a variety of other regs over the years.
Whereas I'm a dive gear nerd, my wife is on the opposite end of the spectrum and has no idea what brand/model of regulator she's using. When I mentioned that she'll be using a new second stage, she shrugged with disinterest. In some ways, she was the perfect evaluator.
I immediately fell in love with the TFX... it was so smooth that I could breathe more naturally. After the first day of diving, I asked my wife if she noticed anything different with the new regulator. I expected another shrug, but she perked up and said its the first regulator she's ever used where she didn't have to think about breathing. She also said there was no going back to our previous regulators. So two enthusiastic thumbs up!