I suck at this stuff I have so much in my head and do not get it all out.
I can confirm the black not reflacting issue because we have a problem bouncing our laser off a black object. The lighter the objec t the easier to get a lock.
I it is really hard to get a good shot in with a hand held laser gun, if you notice a lot of the time they are leaning on something and bracing their arms or hands so they can get the gun really steady.
The farther away you are the hard it is to get a lock but, they must start from pretty far because they need to get a good shot at you. My advice? If you are in front and a warning sounds change lanes quickly and safely. Do not wreck!!
After I got zapped I did a ton of research on this subject, it was really pissing me off.
Good read:
http://www.radartest.com/article.asp?articleID=100541