For those of you with a mini or regular protank WITHOUT the airflow control you can purchase one to turn your tank into one with airflow control. I bought all mine from Sun-Vapers, very reputable, fast shipping. Here is what the base looks like and links are below. Make sure you read the description and the compatibility section to make sure these will fit your Protank.
KangerTech Mini Aerotank Base
KangerTech Stainless Steel Aerotank Base
If you don't want to upgrade or want to purchase a new tank, I would recommend you look at the Aspire Mini Nautilus with the new BVC's (bottom vertical coils).
The Aspire Atlantis is very new (~ 2 weeks old), looks very promising but you need a battery that can run sub-ohm coils AND the tank is very small, will vaporize a lot of juice, and will need to be refilled often. Every "first look" review I have seen on this product brings this up.