1 - 4 Stunden
My laptop got Olympic fever and tried to do a full flip dive off my desk, with predictable results. Cracked LCD screen. Might have taken it to a repair shop, but I was headed out of town to an area without any so I figured I'd give self-repair a go.
It was long. Took me a bout 2 1/2 hours start to finish, with a couple mis-steps along the way that required I take things apart a bit again. But it worked and my laptop is back to normal.
As others have said, do this work when you are NOT rushed or up against a deadline. Work slowly and carefully. In particular, note the routing of cables as you undo them. The instructions are good about screws, but a little vague about the placement of cables when reassembling. Took me a while to figure out how to re-route some of them when putting it all back together. You might even want to take macro photos of some of the steps before you disassemble, for reference on the reassembly.
And finally, use the white paper and scotch tape trick: As you remove each screw tape it down to a piece of white paper and write the step number next to it. Makes it MUCH easier when it comes to reassembly.