VTC6 can be a great battery, depending on your needs (and assuming it's not counterfeit - where do you get your
batteries? Some vendors are more reliable than others.)
According to
Mooch's chart, the VTC6 has a CDR of 15 amps (or a temperature-limited CDR of 20 amps, but as we have no accurate way of measuring the temperature throughout a cell while vaping, we have to use the non-temp limited CDR).
To find the maximum wattage this cell can be used at, the equation is:
CDR x Number of batteries in the mod x 3
So, if your mod is a single battery mod, that's 15 x 1 x 3 = 45 watts. If it has two batteries, it's 90 watts. Note that if you're spending much time vaping near the limit, you'll probably get better performance out of a cell with a higher CDR.