I've noticed a couple of things about who pays attention.
Cops don't. I went past a bike cop monitoring a local speed trap in second gear, doing 1 under the limit, and he never looked up from his report book. Nor has any cop I've ever passed even glanced at me.
Vettes and Jaguars seem to want to come say Hi and wave.
Other sport sedan types are a mixed bag, from a nod and a thumbs-up to a "What [year] is that?"
Ricers haven't paid attention one way or t'other.
Mustang drivers... ah, Mustang drivers. They pointedly, determinedly, most assuredly maintain a blind spot one Cobra long and one Cobra wide. Mustangs of every stripe are plentiful here and I have yet to have one even notice my existence. I think it's a grim acknowledgment that something way cooler and more potent than them is on the street.
My favorite so far is the guy who pulled up next to me in a riced box, something like an Element or Cube. He stopped next to me at the light, stereo blaring. The stereo went off. The passenger window went down. I was fiddling with something and when I looked up, expecting the usual "Nice car!" or thumbs-up, I got "Sorry! Just listening..."