The good - Ergonomically great, slips onto controller snugly and doesn’t affect grip. Buttons have a nice click and are well placed and easy to reach. The gyro is cool feature. The app is very useful for customisation.
The bad - takes a lot of fiddling in the app to get the gyro at a useable sweetspot and this would need to be done for every game if you intend to use it.
The very bad - firmware updates require a PC and it’s a bit of a painful process as you have to update the dongle and the controller pack separately. The big deal breaker for me though, was that the device doesn’t support a wired chat headset. It does work if you connect it directly to the console via USB but then I may as well buy a wired pro controller for a similar price. Maybe this will be fixed in a future firmware update but I’m not holding my breath.