After the protank. I am spoiled. Haven't had a issue, i like the flavor and the vapor production. now just need to get the extra play money gathered to get a couple more for extra flavors i enjoy. I still enjoy my mini nova's but they don't compare in my opinion. One flaw to the protank is the cool vape. I am waiting for a company to make a middle coil. for a medium temp vape. that would be the cats meow there. LOL