like others have said, this should really be seen as a keyboard only and not a cover. However I was after a keyboard first and foremost and have no problems using a separate cover. The keyboards that double as covers tend to be chunky and I would rather have a thinner and sexier keyboard. So far I have found the keyboard a little cramped, and I have small hands. In saying that, a few times I've forgotten I wasn't using the laptop and subconsciously my hands have tried to find the track pad LOL
For my purposes, which is the couple of times a year I need to travel and work on uni assignments at the same time, this offers a much better alternative to the on screen keyboard as it also frees up screen space.
You do need to be careful with both the iPad and the keyboard as they look like they will scratch easily, however as someone who never uses covers with anything I'm used to being careful enough to avoid scratches (despite being a rough person). Just need to make sure you always pick the keyboard up properly and don't let it drag on any surface.
In addition, if you are typing while in bed, remember that the iPad is not actually attached to the keyboard!
This keyboard was the deciding factor in selling my MacBook Air and purchasing a Mac Mini for the bulk of my uni work, with the iPad and this keyboard as a travel option.