it depends on the insurance. insurethebox do have peak time guidelines, but they affect your "Bonus Miles" at the end of each month they give you more miles based on how well you drive, which takes into account, speed, time, alertness etc, plus other bonuses are, if you have a crash with the box fitted, it calculates whos fault it was and are used very often in insurance claims to prove innocence.
my wife has it set up in her new ka, and she gets around 88-90 out of 100 bonus miles each month and now its on renewal its 45% cheaper than last year, and we have had no issues with them at all.