Well it has worked a treat on my car when I did it. I did it because I was about to sell the car so I couldn't sell it with a big rust patch, or a horrible spray patch. So it was like a make or break project for me because if it were to go tits up, than I probably wouldn't sell the car.
AS for using a lacquer, its a bit of a grey area with me. When I used it to spray the spoiler, the lacquer reacted with the top paint and gave the spoiler a horrible spider web like finish. When I did the wing I didn't use lacquer and it looked absolutely spot on. I asked at the local motor supplies if I should get a can of lacquer, but they said its only needed for metallic finishes.
Mig