Jeez. . .My two cents: Your car needs a full alignment and balancing of the tires. If the problem with vibrations continue, you are probably looking at tires with a flat spot. This happened to me on my old LR3. I finally had to get them to replace the tires (which they did and the problem went away).
If they aren't willing to do that work for you, I'd make a fuss. You obviously have some kinks in your steering system. They need to eliminate the basic stuff and see what's left.
If they aren't willing to do that work for you, I'd make a fuss. You obviously have some kinks in your steering system. They need to eliminate the basic stuff and see what's left.