Ok... there has been a bit of misinformation here that is just buggin' me... so I'll correct or clarify it some...
Currently GotVapes does not carry a eGo-C Twist Kit ... they only have the batteries at this moment. To create a kit, select two twist batteries, a charger and your carto/clearo of choice along with a case if wanted.
They do however carry both the eGo-T and eGo-C full kits. The main difference ( besides the battery options available ) is with the type of eGo tank that each come with... the T comes with an all in one atty that uses the tank... the C version is similar but the coils for the atty is modular which makes it cheaper in the long run IF you like this type of tank system, many people do not because they are prone to leaking and have a weak flavor on the vape... An eGo type battery can use either an eGo threaded carto/clearo/atty or a 510 threaded one...
Ok... There are 3 kinds of Phoenix clearo's... The eGo threaded 3ml bottom coil version... the 510 threaded 1.5ml bottom coil and the 510 threaded 1.5ml top coil version. Notice only one of the three is eGo threaded.
The Viva Nova is a 510 theaded tank using a CE2 type of replacably head on it... it is not an eGo thread as someone else mentioned.
The Stardust is an eGo threaded clearo and as mentioned if you get a 510 type of PV, you'd need to use an adapter.
As to which type of kit or PV to go with... this is a tough one because it depends on personal preference more. First you would want to consider how much you vape.... if you are a chain vapor.... a slim cigarette size PV like the 510 or the Volt Karma would probably only last between 45 minutes to 1 1/2 hrs. The 650mah eGo or similar kit would last 4-6 times longer, a 1000mah would go somewhere in the neighborhood of 6-8 hrs .... All of these times are subjective and actually depend on how you vape...
Unless you are a light vapor... I probably wouldn't recommend a slim sized PV but there are still times when these are nice ... say going into a restaurant that allows vaping where you aren't going to be there long enough to vape 1 or 2 batteries worth.
On the little bit larger PV's... I'd recommend one of the variable volt units such as the eGo Twist or Innokin iTaste. If even a little larger in size doesn't bother you... you may want to consider the Bolt and add a Kick to it perhaps... or maybe the Tox Cannon even. The nice thing about the larger units is they have replacable batteries which are much cheaper to replace and will also last much longer than the eGo's or iTaste
There is certainly a lot to consider...
Randy