We have a Honda with similar system. It can be annoying in heavy traffic, but wow is it amazing on long drives between cities. There's no more fighting the cruise control when you and the vehicle in ahead are a little out of sync speed wise - either due to 75mph being a little different in each or due to performance differences on hills.

On the whole, I find a 3+ hour drive a lot less stressful with the adaptive cruise control, and I arrive feeling much less fatigued.