The biggest change for me I've noticed is I'm vastly less likely to speed with a digital speedometer than with a dial spedometer. Adaptive cruise control also helps a lot
(I was never particularly a speed demon in the first place though)
I think a partial reason for that is a ton of cars put 80 in the middle of the dial speedometer. So, it's bizarrely easier to see your speed accurately if you're going over the speed limit.
(I was never particularly a speed demon in the first place though)