I've taken my daughter's iPhone in a couple of times for issues. They have been taken care of right there. Overall, I'm very happy with the service at the Genius Bar.
When you want service at a store you have to get an appointment. Don't be even 10 minutes late or they'll toss you out. I think the genius title has swelled their heads.
I picked up my MBP yesterday with a new LCD fitted.
They had explained they were very busy and quoted 5 - 7 days for the repair and it took 5 days, so I'm perfectly happy with that.
The cost of the repair was £452 in total, which isn't cheap by any means. They had replaced not just the screen, but the cable, housing and bezel so basically all the computer beyond the hinges.