510 at 5 volts is phenomenal, same goes for 901 or 4075 but they always spit liquid out at higher voltages for me. 801 and 4072 are just as good, but I've never had an 801 or 4072 that lasted more than a couple days at high voltage so I don't bother with those either. 510 all the way, they last and don't leak liquid out in my mouth. Done.