[ArnoldP]

Admittedly I haven't used one aside from once briefly in a store, but seeing people balance them on their laps using the keyboard just looks awkward. Like they are top heavy? Or just too small for that purpose, necessitating one to keep their knees close together.

[wlesieutre]

Works fine for me, but I can imagine issues for people with short legs. If the kickstand needs to be out past the end of your knees you're going to have a problem.

[fsloth]

Using a Surface in ones lap looks more awkward than actually is.