I mentioned a day or two ago that my left joycon was raised slightly from the back of the Switch compared to
the right joycon, which is perfectly flush.
I tried attaching it several times at work today and eventually measured it, and I think the track might be slightly off-- it's a gradual decline in height from the top of the Switch to bottom. Tested out a second pair of joycons, same issue.
It doesn't really matter and everything works fine, and I will rarely use it without the pro con, but I'll be damned if I don't instantly go to feel it every time I pick the thing up-- it's noticeable right where your fingers might naturally sit at the back, so of course I've been obsessing over it.
Got a Pro Controller yesterday, (make sure you set it to be the primary controller in the home menu otherwise it don't work) played about three levels of Metal Slug 3 with it, felt really good both with the Dpad and left stick.
I didn't even know there was a primary controller setting. I just pulled it out of the box, made sure it charged fully, and hit a face button and I was instantly connected.