The smart batteries are a gimmick in my opinion. They do however provide a bit of safety for those people that get into the hobby that have no clue about the dangers of LiPo charging, let alone how to care for their LiPo batteries.
To me though, this does a disservice to the hobby, all while lining the pockets of Traxxas and Horizon by way of selling severely overpriced batteries and chargers. Even buying a RTR that comes with these crappy chargers and batteries has the price inflated to the point you can buy a good hobby grade charger and better batteries for the price difference in an RTR sans batteries and charger.
So I have a hard time recommending them to anyone. I have a Spektrum smart battery that I will be cutting the connector off of, or just giving it away. It was a battery Horizon sent me to replace a wrong battery they sent me. Not sure how I can order a 3s battery with an EC5, get sent one with an XT30, then get a smart battery as a "fix" for their mistake, which has an IC3 on it. But I have 2 batteries that don't fit any of my RC cars, and I have close to 30 RC's.