Don't buy the Ferrari and skimp on the tires!
Nice! Sage advice, but that's the beauty of the ProVari, it will work with anything out there.
EGO-mainiac, you are investing in something that will deliver exactly the same voltage/wattage each and every time you push the button. Why not compliment that with something that will deliver the taste and hit you are expecting each and avery time? I agree, the high-end rebuildable atty tanks are outstanding and will pay for themselves as time goes by. The only downside that I see with them is if you want to run multiple juices throughout the day. I know I do. I've tried a multitude of devices so far, and the Vivi Novas work very well with the ProVari, but I found that switching juices can be a little time consuming. If you're good with that, you will be happy with the $12 device, or something more high-end like the GG.
Another angle on the multiple juice thing, go with some inexpensive clearomizers. LordDavon just did a review of the CE4+ clearo, and he gave it a thumbs up.
CE4 Video These cost like $3 and look like they will last a while before discarding.
HappySmoker.com I haven't tried them myself yet, but they look interesting.
So, I guess in a nutshell, vapor delivery is as subjective as juice or other hardware. It's just a matter of trying a few methods and decide which direction you want to go in. I know this kind of goes against the Ferrari allusion, but everyone is different with how they do things, or wish to do things.