Size-wise, the eGo is pretty much between the P10 and P16. P10 batteries are only rated at 350mah. The P16 can use either the 550mah IMRs or the 750Mah protected batteries. I think the P16 is the way to go for you. Even though you will be giving up a little bit in capacity, you'll be getting the real 3.7V experience. The AW batteries will generally operate between 4.1-4.2V when fully charged, and they have a nominal voltage of 3.7. Either way, I guarantee that you'll be happy with any SuperT purchase.