Hiya - I personally love the DAV and have been buying the 1.5 ohm cart figuring it has the most vapor. It must come at the expense of battery charge life. So, my Q is, who has used the 2 and 2.5 ohm carts? Do you notice a diff with batts lasting longer on a charge? Is the TH, vapor that much less? Do y'all mess with the voltage much? TY