I like that it's easy to set up for my team members so they can quickly start using their correct emails instead of having multiple accounts or even worse not knowing who owns what account! It also helps with getting rid of old or unused addresses which was our biggest problem in previous software we were running before this one.
There are some features missing from the basic version (like being able to delete your own address once its been verified) but those should be added sooner than later as there isn't much harm done by them existing now compared to waiting until v2/3 comes out next year at least. We've seen results already - people have started opening more business related mailers via "correct" rather then just spam folders etc.