Just to be clear, I'm not discussing a physical comfort that this brace provides. It's actually just the opposite: annoying, itchy, and quite ugly to look at. I'm referring to the security it provides by preventing me from doing anything stupid. Although I would say that physically my arm has gotten used to the brace I would not call it comfortable.
I started to become aware of this unexpected comfort the first time I took the brace off to take a bath. Actually, to be honest, bath is a generous term. It was more like a half- body wipe down by wife. More on that never.
As soon as I took my brace off I immediately tensed up and couldn't relax the entire 15 minutes I was out of it. This made it challenging to communicate with my wife who was helping me, and also made me want to hurry things up so I could get back in the brace. I'm sure it didn't help that there was added risk in me having a slip and fall since we were in the bathroom.
During the few times I've been out of my brace since then, the fear has gone down but it is still a tense experience. Knowing that my tendon is likely only 3% repaired at this point, the fear of moving my arm in an improper way and re-tearing the tendon is a strong motivator and minimizes the inconveniences of wearing the brace all of the time.
So for now, the comfortable brace wins.