I have absolutely loved copilot so far. I especially love how fast it handles indexing complex n-dimensional arrays, which I'm really bad at. I also feel like often pushes me to more formal solutions instead of hacking. I'd estimate a 10% velocity increase for me with it.
My team was freaking out about copilot because we're conducting tech interviews right now, with a take home exam and some pairing sessions, and they're worried we'll hire a bonehead because he can make copilot spit out reasonable stuff in our contrived and simple interview scenarios.
But we finally had a guy whose take home test had tons of handling in the controller for cases we weren't even using, and test coverage of things that couldn't possibly fail, or were actually part of the core language and not our own code. It was really obvious! And when I wanted him to fix an SQL Injection problem in our pairing, copilot carefully preserved the bug while he was moving code around. Made me chuckle.
Super excited for GPT-4 behind it.