Quit about 3 months ago @5 a pack I've saved ~$450 and I've spent probably ~300 total on supplies/juices so it's working out fairly well for me. To be fair though, I've caught the upgrade bug and I'm starting to buy backups for my backups/tanks/etc, the wife doesnt mind because in the end, my health is more important than saving money.
I usually do a bit of research before making any purchases, so there really aren't any I regret thankfully. Broke my first eGo but thats about it. Thank god I found this amazing forum as early as I did!