We moved into our house last year and wanted to redecorate each room. I used a Wagner W690 to spray all the walls and ceilings in the house, excluding the bathroom and kitchen. I'm crap at painting - particularly cutting in, hence the appeal of spraying to me. We decided to paint all the rooms white - walls and ceilings. In short, this worked very well for us, and I'd do it again over rollering. I'll give some more detail below.
We took all the doors off, stuck down floor protecting polythene, and masked off all the windows, woodwork and electricals with the rolls of brown paper edged with masking tape. It took me about 45 mins to get each room set up. The stairwell and landing was tricker to mask, and took a bit longer.
Spraying the first bedroom was tricky - working out the right combination of air, paint, and paint viscosity. The first practice wall needed rubbing down a bit and redoing to get a decent finish. However, after the learning curve, I could put a coat on a rooms walls and ceiling in about 20 mins, which was faster and less tiring than rollering would be for me. Each room got 3 coats, except one wall that was previously painted dark navy, which took 5 to cover. Having got into the swing of things, downstairs was pretty easy, and I got 3 coats on the living and dining room done in one day, whilst doing some other bits in between coats. I'm happy with the finish, it was better than I would have managed with a roller, and I think saved me quite a bit of time.
The landing, stairwell, and downstairs corridoor were, in comparison, a pain to spray. It was cumbersome and awkward trying to get the gun into the right position to spray, and to keep the movement steady enough to get a good finish. That might just be my lack of skill with it, but it was by far the most frustrating part.
If you are spraying different rooms, or different walls within a room, different colors, then the workload increases quickly - there's a lot more masking and cleaning of the sprayer to do. The sprayer has since been useful for refinishing some garden furniture and other little projects. I'm happy with it and think it was worth the ~£150 we paid for it.