I know I'm not the target audience for these devices because no component of them can be upgraded, but they really do look nice. The industrial design is amazing, the screen of gorgeous, the form factor is perfect, and they do promise a smooth Windows experience (whatever that fairy tale might be like)..
That's why my wife has a Surface Book 2, and we've had no end of problems with the thing.
The power supply is inadequate. It's rated below the TDP of the components in the laptop. Plugged into the wall, it will slowly discharge if you're beating the hell out of it. And, if you do that for long enough, the power supply dies. We're on #3 in about 18 months.
The "Surface port" doesn't have great physical registration between the two halves of the device. It'll eventually wiggle into a partially-seated state, with the devices in the lower half hopping on and off the system bus. The fault can be cleared if the device can get into a good state for long enough to detach and reconnect the base, but to do that, the battery charge has to be just so. Since this state sometimes makes the charge controller not want to take a charge, a reboot is often needed.
Support from Microsoft has been less than enthusiastic, and we're not even out of the warranty period!
Meanwhile, my gigantic Thinkpad cost about half as much, deigns to allow users to upgrade memory and storage, has a charger nearly stout enough to chock a wheel, and Just Keeps Going. Horses for courses, I guess.