Chris, these are lovely! I've seen your work before but I cannot for the life of me remember where.
First one is really nice however, either my eyes are deceiving me or, the car is shot from slightly off centre making it looked skewed? Could be the wide angle I guess!
Second is absolutely stunning and my fav of those that you have posted.
Third is awesome, look at those colours pop! I should really invest in a longer rig, you've got length!
Fourth is the most 'medioker' of the set but not in a bad way, comp and lighting are spot on...as usual!
I take it you're diffusing the flash?