I just started recently and I'm looking at a VAMO or an iTaste from FastTech, but my first kit and the one I use ATM is an eGo-C2. To be honest I don't know if it's a twist or not, but it has that (useless IMHO) variable voltage orange button setting.
The Vivi Nova, great choice. I don't have an original "Vision" but rather an aClear, but it was great, until I found the victory tank which is what I'm using, but the 2ml one (and that is not enough so much, so I prefer the Vivi with its 3ml capacity).
I have to say this was the best impulse buy ever, literally I received the package, smoked my last cigarette and embraced vaping completely. Pack-a-day smoker before that.
I will get something to compete with the Victory Tank soon, so to test new stuff and get comfortable. Will probably also order some big monster type VP form FastTech (the iTaste monster-something).
I personally don't plan on trashing the eGo-c battery once I get a vamo or so... I will probably use it for emergencies or for cases when I need to get into an airport for a trip or something and in case they tell me I cannot take it with me I'll simply put it in the closest trash, instead of ditching say my future VAMO or whatever.
The resistances you will need to experience 1.8, 2.0, 2.0 and so till you find the one you like the most in terms of flavor, battery use, vapor produced, and so on. I think anyway with the eGo you will be limited because unless I'm terribly wrong it cannot set a voltage like on a VAMO or an EVOD and such.