Brydge Wireless Keyboards for iPad Pro 10.5" / 11" / 12.9" - Various Prices

I use a Brydge. The clamp is rubber and I don’t see any scratches on my iPad. It clamps outside of screen area anyway.
Reviews say the rubber that lines the clamps may fall apart - Mine is starting to come loose a little bit but it still stays on and serves its purposes of clamping and protecting the glass. Just be a bit careful putting it in, so you don’t tear the rubber any worse.

It’s heavier than I like, but it’s about the same weight as the new Apple’s Magic Keyboard for iPad Pro.

Using it is a dream as you can position the screen at any angle, even 180 degrees flat. Or reverse mount it so that the screen is closer to you and keyboard hidden.

Oh and it works in both wireless and wired mode. It charges by USB-C, so doesn’t need a second cable at all.

I use it as well, the rubber started to tear apart a bit after 4 months use, I did not even pull the Ipad pro out that often and it already start to tear apart. It indeed serve the purpose of a nice keyboard, especially like the feel of typing.
It's heavy, however thumb up for 180 degree flat positioning. I did some research on the new magic keyboard, apart from that trackpad I did not see any other benefit, especially the lack of function keys as the top row that Brydge. Brydge also has the keyboard with trackpad, but not even close to Apple's, will keep the one I have now, using it on daily basis with magic mouse.