Looks interesting - displacement/deform on left side looks a bit artificial. Light is also too focused. Either increase cone angle and/or move it further away, or use a directional light source.
Mustang: sweet lights should be chrome and not gray (as they appear to be atm).. imo.
You need to use the alpha channel from tirewall map, to mask away unnecessary area - underlaying material must be idendical with rest of tire, and then you won't notice any seams.
Bose321: It was quiet easy, really. A long reflection plane above the cars, but not covering the entire car width to create the rim light effect, and then a spot light to "floor" the cars. Looks a bit like bottom of the XRT is lid in the big render, but thats just another example of me being lazy (reflection is a simple copy paste in PS, and didn't want to offset it too much)
It was easy because same setup worked for all cars - had to move the reflection plane slightly for the FO8 though, as it picked up too much from the plane.