The reviews have been favorable, however it contains Minoxidil as the active ingredient.
The drawback is when / if you stop using Minoxidil, your hair growth will regress. It will begin to fall out.
http://www.virginiahairtransplantsurgery.com/blog/pros-cons-minoxidil
Con: You Need to Be Consistent
You can’t slack off if you’re using minoxidil to regrow your hair. The treatment only works if you apply it as directed. That means using the product twice a day, every day.
Once you stop using it, the hair will stop growing and new growth will fall out.