[ltd]

Over the last 15 years, I've driven probably around 100,000 miles in the USA, and have been pulled over several times but never for speeding.
If keeping up with traffic, the police won't even look at you.
If you tailgate, or undertake anyone, they will pounce on you.
If you're a single male occupant in a vehicle (like I am many times) expect to be pulled over as they profile and target people they suspect (on the interstate) of drugs and drugs related offences.
Luckily, our accent carries a lot of sway, and the troopers are generally very nice once they establish you're not up to no good. I've even got a photo with one from Illinois.
Down in Texas though, they're the best troopers around.
On the highway (not interstates), I've had a Lincoln Towncar on cruise control at 104mph. Went straight past the trooper, he did nothing. In fact, oncoming traffic would pull away from the centre line to prevent the oncoming wind buffet effect from popping windscreens. Awesome country to drive in the USA, and great scenery too.