I actually love my Joy-Con. I have even refrained from buying the pro controller because I like them so much. The sliding on and off from the console feels great. On the console they keep a slim design that, while not an ideal grip, allows that signature Switch portability. Off the console, I rarely use the packed-in adaptor that simulates a more traditional gamepad; I enjoy having a controller in each hand and laying back like a king while I'm fed grapes by my attendants. It's an awesome feeling.
The biggest gripe I have is the Bluetooth connection. I have a hard time understanding why I can walk into another room with other gamepads and maintain connection, while I sometimes realize I've accidentally blocked my Joy-Con because I propped my foot up on the table or, God forbid, leaned back further than six feet from the console (not an exaggeration. I've done tests). That being said, even this was not enough to stop my effusive praise of the Joy-Con to anyone unfortunate enough to cross paths with me. THEY CAN BE SPLIT IN HALF, ONE FOR EACH PLAYER, I shouted. THE COLORS ARE SO PRETTY AND YOU CAN MIX THEM, I foamed.
Then... They stop working. I have three sets of Joy-Con, all three in different colors purchased at different times, and all three sets have eventually succumbed to drift. This is not a small problem. The darn things just send your characters all across the screen if you take your eyes off of them for even a moment. I would send them to Nintendo to fix them, but living in Korea complicates the issue, an issue that shouldn't be there in the first place. I ended up using electrical contact cleaner and it fixed the problem for a bit, but the process has to be repeated regularly. Good thing I bought the venti-sized can, I guess.
Final thoughts: a revolutionarily flawed device that I lovehate.