I love cars too. Not as much as a good sunset, but definitely love them old, old and well restored especially. I shot these with the intent of showcasing the shopping area of my master planned community maybe with the intent to sell them... to the community association if they were interested. No buying but they liked them.
f2.8 is where this lens starts to really shine. Really tempted to pick up the new Pentax DA 50mm f1.8 at some point, the rounded aperture blades will keep me from having the octagonal specular highlights in the background.