I started out with a 510 clone, just got an eGo mega (love the batt, hate the attys and carts), and I just got a 510 passthru. Who knew the taste could be so different between the 3 of these units! 510's great but the batts dont last long, nor do the carts. eGo mega batts are the bomb! I have taken to using my 510 attys and carts on it, works great, great vapor great taste, a bit more taste that the standard 510. 510 USB passthru... holy crap. I thought my Hypnotic Mist was yummy before, but WOWWWW!!! this passthru somehow magnifies the flavor in such a yummy way! DAYUM!! This will definitely be going to work with me next week. Cant wait to try my new batch of Hopscotch on this baby! I think I'ma upgrade to the 510 mega attys and carts and I'll be set whether I'm using the USB passthru or my eGo mega batt.