This Surface Book 2 is fabulous! It is a fully functioning Windows laptop, and then the screen detaches to become a tablet. I almost bought the 13 inch but am so glad I got the 15 inch. Even at this large size the tablet only weighs 1.8 lbs. I read a lot of pdfs and kindles and enjoy the large screen size. As a laptop the battery lasts 11-13 hours; as a tablet 5-8 hours. The only issue I had was a weak "touch" but this was adjustable.I bought the "Renewed" version on Amazon from seller Integron Tech. (Re the 90-day warranty, I bought the 4-year extended warranty to be on the safe side.) It looks brand new and appears to be renewed by Microsoft, not some 3rd party. Just fyi, every computer I've bought in the past 15 years has been refurbished/renewed, and I've never had a problem. The secret is to buy factory-renewed - send it back if it is not! So far my Amazon purchases appear to be factory-renewed (per the packaging). Also I suspect "renewed" often are brand new, just reducing old inventory, but this is only a theory.Also look at the price where you expect to see it. If you see another price (cheaper) on the same page (probably marked "used") do NOT buy that one. I suspect some of the bad reviews may be for these "used" ones which come and go -- who knows what the condition might be. The renewed product should appear brand new.Note: this is a copy of the review I wrote for another 15" Surface Book 2 about a year ago. I have been so happy with it that I bought a second! This one has double the storage (512 GB vs 256 GB) but is otherwise identical. For my own needs, the smaller storage was fine, just happened to get this one re the price.