1 - 2 uren
iPad, meet five year old; iPad meet floor.
Glass was shattered to a crazy extent. The entire front surface was literally small shards of glass 1/4" or smaller.
Well. It took about 2 hours. 85% of that was spent removing glass. Unfortunately, I was not able to follow the guide step by step, but rather used it as a means of avoiding damage to senstive components like the wi-fi antenna. Plastic tools were all completely destroyed by the end.
The glass panels are very brittle - even a little bit too much pressure or a hint of torque will send little shards flying. Prepare for slivers of glass everywhere. Do not take the guide's warning about safety glasses lightly - had I not worn a pair, I would likely be blind right now. One snag that I did run into, was failing to insert the digitizer cable far enough on the first attempt. It's fiddly, but make sure that it's all the way seated or it will perform inconsistently - if at all. As a corollary, make sure that you do a dry fit of the new panel (i.e. start it up with the tape still on the adhesive strips) so you can verify that everything is in order. Finally, be careful routing the cables when reassembling - if any of them are out of place, it will prevent the glass from seating and sealing properly.
Although this repair is considered difficult, it's should be doable for most people - it really just requires a lot of patience and decent mixture of force/finesse.