Knowing exactly which lane you're in and the actual speed limit of that particular lane can be tricky for an automated system, at least in any of the systems I'

Knowing exactly which lane you're in and the actual speed limit of that particular lane can be tricky for an automated system, at least in any of the systems I've seen implemented. I've had cars with both automated speed limit sign readers, GPS+map databases, and more show me two different speed limits and neither one was actually correct for the lane I was in. This is a somewhat common occurrence on the highways around me.