I gotta second (third, fourth...what are we up to now?) the Kanger series. The mini-pro has been a solid performer for me on the eGo setup and with a 510-eGo adapter, works well enough on a mod. I also like the eVod style for sampling, stealth vaping and times where mobility reigns. I also have a Pro-Tank, but it's a lot more finicky than both the eVod and the mini Pro-tank.
It's a pretty economical system if you can take on rebuilding the coils. You can usually do a much better job than the factory and it doesn't take a huge investment to get started, depending of course on how "pro" or experimental you want to go with it. I didn't find it all that difficult at all, but some people out there struggle with it. The beauty of the above triad of heads is that they all take the same style atomizer, so you can have different heads for different purposes and you just have to learn to rebuild one system. I have found the Pro-Tanks prefer a slightly different wicking than the eVod and mini-Pro, as for some reason, they're more prone to flooding than the other two.
I've been playing recently with ekowool in the Kanger coils and I think I prefer it to straight silica. There was something about the cotton that I didn't care for as much, probably the difficulty in getting just the right amount. I'll still play with cotton as many swear by it, but silica and ekowool are both consistent and straight forward for rebuilds.
