Sleeper shells

[Kalaehina]

Anybody use one of those sleeper shells? The ones that look like a camper shell that's been cut short, like only a 1/4 of the length of the bed? If you do have one, do you actually sleep in it? I've always wondered if it's comfortable. Only because I sleep about 45 minutes to an hour every day in my truck, which is not too bad considering I have a regular cab and I'm 6 foot 1, Sorta cramped but I can still get comfy. I was wondering if those sleeper cabs really are sleepable? Just curious, not really thinking of getting one, but who knows??