does anyone have an opinion about the joye eGo cartos vs. joye genuine 510 cartos? i order from cignot and recently upgraded from a 510 to an eGo. i have just been using the genuine 510 cartos and they working fine for the most part aside from occasional leaking and accidental overfilling. i saw that the eGo specific ones were more expensive (almost twice the price), but they look identical in the diagram. can someone tell me the difference, and if they are worth the price difference? thanks...