I've had my Magic Keyboard for over a week. I got my 12.9" iPad Pro (first a refurb 2018 and then returned it for a great deal on a 2020) and the Apple Pencil and a regular Smart Folio (no keyboard) two weeks earlier. I was amazed that whole time at how the iPad Pro was like an artist's palette in my hands with infinitely more capabilities. It seems to have finally started reaching the potential that Steve Jobs alluded to a decade ago. I used it like a larger and enhanced version of my iPhone for practically all of my iOS apps and discovered a few more great ones like Fastmail (which I used on the web or through Apple's Mail app before) and Over (a great, graphic design app perfectly suited to the large screen and pencil). Apps like Things 3 look great on it because you can see more information at a glance. Apple's own Calendar app, the main reason I bought my first iPhone in 2008 to replace my Palm Pilot, is finally useful in the monthly view since you can see all of your appointments (what's wrong with a list view on the iPad Apple?).
Since getting the Magic Keyboard though, I haven't used the iPad in "tablet mode" much. It's relatively easy to take off (albeit a bit clunky, like opening and closing the keyboard is) but just like my Macbook Air, which has been in clamshell mode for 3 months while I use an external monitor and the "old" Magic Keyboard and Magic Trackpad 2, things tend to stay where they are. Your iPad is going to live on the Magic Keyboard most of the time if you get it and it will change the way you use it, not necessarily for the better. It's definitely a great keyboard, but there are a number of minor annoyances that keep me coming back to my "desktop" setup. Some have been mentioned before some not:
-no function keys means time wasted digging through menus, Apple's lackluster iPad OS 14 update did nothing to help here,
-the trackpad is just too small, maybe 2/3 the size of my 2013 Macbook Air's, you can crank up the cursor tracking speed but this is a tradeoff, the Magic Trackpad 2 is 300-400% larger, with a touch device Apple probably thought this limitation would be offset by the ability to use a finger or the Apple Pencil as well (which goes a long way to helping with the "gorilla arm" problem)
-the extra USB-C port for charging is great, but for some reason it's a really tight fit and I've felt like the connector was about to break when removing it a few times, Apple really needs to figure out something like their beloved magnetic connection from years ago
-perhaps most importantly for me, even though it's marketed as a "full-size" keyboard (on the 12.9") it's slightly narrower than the bluetooth Magic Keyboard, maybe 1/2", so it feels more cramped than what I'm used to, I'd love to see Apple finally update their external keyboards to the latest design
So I'm on the fence about returning the MK. It's the best keyboard/trackpad combo for the Pro, but it has it's limitations and when I'm at home there's no question about me using my familiar setup for most writing, editing, etc. over the iPad combo. I can type a quick reply to an email or a note on my iPhone. It may suit you as a mobile option once things open up again, but for now it doesn't make a lot of sense for me to have it sitting on my desk, especially when it discourages me from using the lighter setup of just the iPad, Smart Cover and Pencil. Maybe once iPads become lighter they can figure out the design challenges to make a keyboard with a bigger trackpad, easier opening/closing (it closes with a disconcerting thud) and function keys. If Apple made it possible to connect more than one device to their bluetooth keyboard/trackpad they would offer much more versatility. Right now I would have to buy a separate Magic Trackpad 2 dedicated to the iPad, unpairing from one device and pairing to another is way too slow and clunky.
I may have just convinced myself to return it and wait for either a steep discount or version 2.0. I've put the Smart Folio back on the iPad and will use it like I was doing before to see if I miss having the keyboard and then make a decision before the return window closes.