This is fine for the price, if you're satisfied with the relatively low voltage of the standard ego (I usually am, using LR cartomizers). The build quality is pretty good, but I highly recommend using something to lube the threads since it's aluminum. My local hardware store doesn't have Noalox, but recommended something called Oxgard, which appears to be similar. The fit for a couple of my 18650 batteries is very snug and, as mentioned elsewhere, there are no vent holes. I plan to drill a couple just to be on the safe side. The main reason I bought this is that the battery can be charged while in the unit using a regular eGo-T USB dongle. That means that when I travel I can just use the wall warts I already carry for charging my phone, Nook, and iPod. Big plus for me not to have to lug a dedicated 18650 charger as well.