I can't speak for the car sales side of Magness, but I had a very disappointing experience with the service department.
After having some errors show up while driving my Prius, and not being able to start the car's gas engine, I had the prius towed to Magness. This was my first time taking a vehicle there for service. On the phone I was told that the codes showed a P0AA6 "Hybrid Battery Voltage System Isolation Fault." They initially said the car had several other issues. When I asked about what they were, the serviceman told me "oh, the guy who checked it out has just been doing this awhile and is worried about potential issues with the Inverter, and other parts of the hybrid system." He wouldn't give me any other info on the car or potential issues. However, he did tell me that I needed to replace the hybrid battery and gave me a quote of $3600.
Upon arrival at Magness I paid the $40 service fee, and decided to try again to ask for more details. The serviceman told me that "replacing the battery has a 50% chance of solving your problems." He proceeded to tell me that basically the car could have other issues, but they can't look into them until I pay their $3600 to buy a Toyota issued battery. The serviceman also wasn't sure whether it would be a refurbished battery or a new one: "just whatever we get from Toyota." At that point I knew I would not be spending any more money there. I probably would have gotten better info towing my car to O'Reilly's. The icing on the cake was when the serviceman gave me the key and pointed out a car in the lot that wasn't mine (my car was in the opposite direction, in a hidden area of the lot). Of course I told him this and he eventually found out where mine was.
Basically, I left work early to pay $40 to be told that they can't look at my Prius because it has an after market Hybrid battery, and that there's a 50/50 chance that replacing the battery with "whatever Toyota gives them" for their $3600 will solve my problems. I left with nothing but a receipt: no proof my car was even looked at.