I’ve had every iteration of the BT20 series and this is by far the best of the bunch by a long shot. It’s more comfortable in the fit with the ear hooks being softer and more pliable. The built in amp drives better at lower volumes (where I’d have to be at 80 to 90 percent volume on the BT20 I only need to be at 40 to 50 on the pro) the charging solution is a million times better and more convenient. I’ve tried the case with a pair of BLON 03s ZS10 pros and Legacy 3s and all of them fit perfectly while connected to the hooks. This changes once you try to add a wire in the case as well but it can still fit if you disconnect the items and sit them flush in the case. They connect pretty much the same as previous versions on first pairing but after that they auto connect as soon as you take them out the case. And the shut off as soon as you put them back in the case. The convenience and improved driving capabilities alone make it worth the upgrade to me.
Only complaint I have at the moment is that you STILL can’t control volume on the headset and having replaceable ear hooks only makes sense if you can buy them separately . It’s not going to give you better sound quality than an es100 or BTR5 but this is for those times that you want better than typical crap TWS sound quality but can’t or don’t want to fiddle with wires of any kind. This is my go to for work listening.