Firstly, I still own a rotary (a Leica) but as I no longer need to set out large areas, like sports halls, and I have never been a ground worker, it is pretty redundant these days. The case and tripod for that unit are simply huge. In any case for most of the work I do which needs to be done to a datum, there is a datum already on a wall for me, set by the site engineer or surveyor using a total station or at least a dumpy level
Pole? Tripod? Are you serious? Who the hell uses those on most jobs? Or maybe it's just the environments I work in. Ever heard of magnetic mounting? And as for "case", my laser is small enough to fit in a pocket or inside a foam insert in one of my Systainers. The fact is that you simply can't carry a 2m Stabila round as easily as a laser, especially when you need to climb 6 mill height floors with it like I do at times. BTW I'd love to see you take your datum line across a room with a level where there's an 8ft section of floor mIssing
As to accuracy, it is relative - I've worked with my fair share of trades (especially brickies for some reason) who think that a cheap, abused 3ft level with a bent bubble is as accurate as a well treated 6 footer, and who can't read the bubble in any case (sometimes because the vial is carp, e.g. on Forge Steel levels). A level is only ever as accurate as its' user, I'm afraid, but the same is true of lasers