I could not get fingerprint reader to work until I made the jump to windows 10. then the option for "Windows Hello - fingerprint" showed up in the Accounts / Sign-inOptions page.
I'm a big 8.1 fan. so this was a bitter pill. I may return it for a non-fingerprint version (prefer red anyway) and then revert to 8.1. that said, I do dig being able to just press the fingerprint key instead of sketching out my doofy picture password...PIN's not too bad though
New keyboard is such, such a big improvement. so much sturdier; does not bounce; space between keys eliminates fatfingering; VOLUME BUTTONS; I could go on for awhile. most importantly, it is just wider and i think now full-sized (previous model always felt just a teensy bit small. someone said it is exactly the same dimensions as Surface Book keyboard, which means no compromises this time around. Many reviewers say it is the best part of the SP4 (ironically you don't need to buy the SP4 to get it!).
I never use the type cover with the Dock, but if it doesn't work that's a bummer.
right now i'm using it on my lap with the magnetic bit locked to the screen. I don't have my sp3 keyboard nearby for comparison, but I would say that the attachment feels a bit less strong with the new keyboard. not a big deal as I prefer having it lie flat on a tablet.
Ironically, a few reviewers say the Surface Book is not entirely lapable because it is topheavy and tends to slide off of your lap (not enough rubber feet?!?). If the SP3 with new type cover is sufficiently lapable, that will be quite ironic...