I have the Factory CD that lets you access the on-line manual. Personally, I hate it, nowhere nearly as easy as just opening up the book and sitting it on the fender, wherever, for quick, instant access/reference and not worrying about your laptop taking a dive onto the floor, having signal, etc.
Plus, this old-timer finds it much faster to use the Index and just flip through the books to the section/page I need than using GM's disc, especially with a couple of sticky note bookmarks or two to flip back and forth between related sections/procedures than trying to do that on the laptop.
Why I'll take a parts store with a 50+ year old person and a row of thick parts catalogs on the counter than a big chain with a some 20-something and the computer trying to look up an obscure part (Like the fuel sender/pickup for my 95 HD2500 C/C diesel with the large side tank. Local parts store old guy found the correct one right off the bat for it in one of his books, when two different Big Chain 20 somethings on computer couldn't, both said it didn't exist!) for an older vehicle.