Hey Dave,
nice render although it's a little too dark

and the car is too big. On Prykies' image it's getting in the right direction (light wise) - but well maybe you wanted it like that. Anyway the backplates weren't post processed and focused on the HDRI position. The files are getting too big in raw, so we will use smaller jpeg for export. You should take care when editing the backplates in 8bit, the sky for example has lost a lot of white balance. You can move the car more back in order to match the focus^^
Hope to see more renders!!
Cheers,
exidge
Ps.:
Duron did these renders quickly: