I live in Va, just not that part, and the rule of thumb is anything less then 10mph over and you generally won't get a ticket. The only exception to this is places like school zones.
That's generally the same in Michigan unless it is a subdivision/residential area, but even then it's rare for a cop to waste the time. It's possible to get a ticket for going 1-5 MPH over the limit. It's described as a "we can find a reason to pull you over for what we want to pull you over for but do not have enough evidence to do so" such as you're having done something suspicious at a known drug house or someone calling about how many drinks you've had at a bar despite you not driving suspiciously. It's crap, but it's common.
Most of the time people receiving the 1-5 MPH tickets are receiving them for violating the speed well beyond that amount (with the actual clocked speed written on the ticket). This encourages people to just pay the ticket without fighting it since they've been given a much lower civil infraction and it makes it a lot harder to succeed in court since the judge knows "radar calibration/accuracy" is much less likely with the written, clocked speed.
My car can warn me if I exceed the local speed limit by more than a set amount. I had to turn it off after a while, because it was just getting annoying on 495.
It's pretty funny to drive back into the city from points west on I-66 as the speed limit drops 70-65-60-55. I usually maintain a steady 7 over and that makes me go from one of the fastest cars on the road to one of the slowest.
I use it for dev to more closely mock prod, as well as ensure repeatable builds. It allows me to run all the services we use locally without a separate vm for each.
