They look nice, although they're not automatic. But, I do know that anything that says "Joyetech" on it is going to be fairly costly. From the size of it, as apparent in the pic, the ARO Winder 900mAh is roughly that slender, and the Mini Protank II is exactly the same width -- you could probably buy two complete sets of those two items for less than you could buy one Joyetech 510cc. And the Mini Protank II is a VERY good-vaping tank, for being that small.
I have one of those ARO Winder 900mAh batteries, and though I was a bit concerned at first about the low-ish mAh rating, it actually compares very favorably in charge-time to other batteries of that size. I like the 900 mAh version better than the other Winder versions, because it doesn't have that "collar" where the button is -- there is no collar, the button is right on the body of the battery, like the 510cc.
Andria