I recently dropped my 3 year old unlimited plan for 10GB shared plan. Just in case you haven't realized, they throttle you HARD after 5GB, which makes it pretty much worthless for me. I rather be able to use mobile hotspot legally and not be throttled every month and save a lot of money.
The benefit of unlimited 5GB is that even though they throttle you but they won't charge you extra if you go over 5GB. I consider it as a friendly remember that I reach my allowance without paying penalty for going over.
with 10GB share mobile plan, they don't throttle you but they will charge you once you are over 10GB and it adds up. if you pay attention to their alert msg, then it is ok. for wifes and kids, that is a problem since they don't pay attention to this alert msg.