As long as you coil for the output of a mech, you can vape at any wattage you want. What matters is how you achieve your target resistance. I.e you probably won't get great results if you aim for 2 ohm with 24 awg wire. Way too much coil to heat up with not enough power to do so. Main (practical) difference from high-powered regulated mods is that you can't simply up the wattage to fire up any halfassed half-ton chunk of coil.