Just back from Memphis and everyone I met from this tour group was fabulous. Friendly, courteous, informative....at the end of one of the tours the bus driver knew I wanted to see the ducks at the Peabody and made a special side trip to drop me off then dropped everyone else off at their hotels and came back, was waiting for me outside - Love them!
As a side note - doing the Graceland tour, they do not get you into Graceland until around 11:00, so if you are doing the full tour you won't have time to see it all - planes, cars and lunch if you have other tours planned. When they pick you up at the hotel around 9-9:30ish, you go to their office while they collect everyone else and you buy your ticket and then wait til they board the bus, which is around an hour wait. I think they should start earlier so you can get it all in, but FYI.
Otherwise, I enjoyed my one day in Memphis and they made sure I had a great time.