I don't have the i-stick either, but if you want to upgrade I'd suggest get a device that will deliver you at least 30 watts maybe 40. The way things seem to be going now with sub ohm clearos like the
ego one(20 bucks)
or the Atlantis, I think it's the way to go. Got both the one and aspire atlantis the other day and the
0.5 ohm coils are wonderful performers. My old provari can't fire them so on the shelf it goes.
I probably won't vape anything over 1 ohm or so ever again. They've ruined me for everything else!
But I'm a much happier vaper today than I was last Friday.