I sent in my 5DMKII recently to have the sensor cleaned and focusing screen cleaned, and it came back with still a few lint specks on the focusing screen and, in the middle of a shoot popped out. I had to use my finger tips at the time to get it back in, I had no tools with me, and I think it got dirty again. Guess I'll be contacting CPS to have a new one put in again, and hopefully won't have to use my 2nd cleaning voucher.
Bummer. I've been pretty happy with the cleanings I've had them perform.