I sometimes get together with some friends I have in common with a relative and in those events, this specific friend which I will name Bob.
When we want to go somewhere, Bob always offers a ride, because he is the only one of the group that has a 5 (five) seater car. He offers it for free and always rejects any kind of contribution to gas and other related costs.
This would be good and I always appreciate the kind gesture but... he is not the best driver and I don't feel safe when he drives.
I even comment with him some of the situations that happen in the trip but he just has the reaction of "laughing it off" and it didn't matter...
I would like Bob to know that I prefer to take my car (2-seater) to the place and I want him to know why. I would appreciate a graceful, non rude way to tell him. How can I do it?
What I tried already: Last time, I told him I would be there earlier because I had to buy some stuff and the mall (which I had to and it was the place where we would meet) but he offered to go earlier and Bob eventually carried us all there. This isn't the approach I wanted but that's what I remembered at the time...