Just got my IBT, interestingly the cartos that came with it are better than the ones I was using. Was using XL one hole smok's dual coils(didn't know they were XL). So, when I got my standard tube and cartos I was surprised how small they were, but these single coil with two holes seem to make the juice taste better. I don't think a tank can do that (so thinking its the cartos, correct me if I'm wrong), but I do like this tank a lot better than the one I was using. Though my only complaint is how messy it is to fill with that drip tool, but hopefully I'll get the hang of it and stop wasting juice/making a mess. I also wish I had known mine was XL, but I'm happy enough with the standard.