I quit giving flight reviews simply because it exposes you to liability that I just don't need anymore. I did one for a guy who was upset I wouldn't sign him off for an IPC. He was in his 70's. I did his FR, and he quit renting from where I was instructing because "I can fly IFR just fine! Why won't you sign me off?!?!". About 4 months later, he ended up running an airplane out of gas and crashing it in the desert. He survived. The only thing that saved my butt when the FSDO came knocking was the records I had kept about him. I make every student do a pre-solo knowledge test for a flight review because it covers all the areas we hit in the flight review like performance, cross country planning, etc. They took them about 20 minutes to look over his file. They took photo copies of a bunch of stuff and said, "If we need anything further, we'll be in touch." That was the last I ever heard.