Setup is reasonably effortless, although I will not specify the embarrassing amount of time spent before I found the icon to bring up the virtual reality keyboard with which to type my Steam credentials. It seems to me Valve could also have done a little more polishing work with the UI in specifying in advance just which desktop you're going to bring up when you choose "desktop" in the bottom menu, either the one on your big tethered PC or the dinky KDE one built into the headset. It's not entirely clear without close observation when you're tethered to your PC and when you aren't. Still, it was a pleasant surprise to find that this is running KDE in its standalone mode.

The Frame is significantly smaller and its weight is better distributed than my Reverb G2. Valve has, however, made a notable omission in failing to accommodate Spheniscidae and allies, as there appears to be insufficient IPD adjustment range for species lacking binocular vision.

Still, I persevered. Probably to the chagrin of my wife, as we prepared dinner with me wearing the things in passthrough mode like Sterling Archer and his night vision goggles. (Which you can use these as, after a fashion, albeit only with a very short effective range.)

Other observations:

The controller tracking is noticeably better than my Reverb G2. I like this a lot. I wonder how much the inbuilt accelerometers help with this.
The capacitive surfaces all over the controller are certainly interesting, but apparently impossible to avoid and I can't find where to turn them off. This is largely academic, other than resulting in you doing various hand-jive actions in e.g. Half Life: Alyx even when you're just standing there holding the controllers and not pressing any of the buttons.
I was ready for the lack of a charging adapter in the box because I'd heard about it in advance... repeatedly. But this still seems like an ill-advised omission. Dedicated nerds will of course have any amount of 30+ watt charging bricks already lying around the place, and I certainly do, but normal people won't and this seems like one of those things that would ruin somebody's Christmas morning if their parents weren't paying attention. At over $1000 already for the base model, I'd doubt that including a cheap charging brick in the box would have broken the budget. As it is, the Frame isn't actually ready to play out of the box.
All of the preliminary reviews were right, and the controller binding menus are a five alarm dumpster fire in a blender. If Valve needs to work on anything to improve the software, it's this. Completely notwithstanding all the various modes to emulate different controllers, which you may need a PhD in PC gaming to comprehend, just figuring out how to swap two button's actions in the game you're currently playing is way too complicated of an operation.
Inspection of your own mug in a mirror via passthrough mode reveals that the front panel is not truly opaque. While it looks black, is in fact completely transparent to IR. Under the IR illuminators in the dark you can see the circuit board through the front of the headset. I imagine this is made of the same stuff as the little windows on the front of TV remotes.
Using the headset in passthrough mode will reveal every blasted bleeding blinking IR source in your house, including all the ones hidden in your electronics for no identifiable reason. On that note, having a reference point for orienting and centering yourself in your VR play space quickly might finally be a good use case for your Wii's sensor bar, which otherwise hasn't seen any action since 2011.
Somehow the thing can show you your defined play space's area outlined on the floor even if you walk away and into other rooms of the house, up or down stairs, and through walls. And it remains perfectly correctly positioned throughout insofar as I can tell, which is deeply uncanny. In light of this, if somebody out there has to have a detailed floor plan of my house I'm gratified it's Gaben rather than Mark Zuckerberg.
The speakers are clearly audible to other people in the room. A word to the wise for anyone hoping to peruse their library of Horny Games in privacy: Use separate headphones.