People in this thread have made some great points but I can't say I agree with them all based on personal experience.
Not being able to appreciate a high end device after a week of vaping - I can't say I agree. I appreciated it enough after 5 days of vaping that I ordered a second one. It doesn't take a vaping expert to experience the clear contrast side by side. More vapor, more flavor, warm vapor(if you like) and throat hit. Find the excel chart on here with the range of voltages used by different resistance coils and experiment. The difference to me next to the EGO-C I used for the first 3-4 days was night and day. The EGO-C is not bad and many people will be happy using them for years and years. My parents for example don't want anything else. The EGO-C is all they ever want to use.
This second point is a personal opinion and reflects my personal experience. I'm wary of devices that I put near my body or face that have the potential to explode. The Provari had the right safety features for me personally so it was another reason to pick one up. There is a really good post about safety in this forum done by a moderator with a lot of useful information. Here are some points from his post (
http://www.e-cigarette-forum.com/fo...61-exploding-mods-update-february-2012-a.html) :
Current advice
So that is the basic information we have at this date. As a result, the following advice can be given at this time:
For ultimate safety, use a single-battery mod.
For high-voltage, use a single-battery mod with a booster circuit of some kind.
No APV with full electronic control has been implicated so far, so statistically these appear safe. You might want to play safe, though, and consider one with gas vents.
Use the best and most expensive batteries you can get. It doesn't seem worth it to economise on batteries. Our opinion is that, at this time, the AW IMR 'red' cell has the best reputation. It is a lithium-manganese 'safer chemistry' cell that does not need the integral protection circuit a Li-ion cell needs. Although these have never been known to explode, no lithium battery, ultimately, is absolutely safe: they will certainly meltdown with plenty of heat and flame if abused; and if they were sealed into a perfectly gastight container, and then made to fail, an explosion might result under those particular conditions.
We know that using a two-battery metal tubemod is intrinsically more dangerous because these are where the explosions are.
I won't repost the whole thing here because I've included a link to the post. It's a good read. It also mirrors my own experience in the RC world. The two times I've seen other peoples batteries go nuclear the reasons have been the exact same as in this post. Stacked batteries of low quality (Granted in the RC world LiPo batteries were being used which are slightly different).
I'm not suggesting other mods are unsafe. NOT AT ALL. I'm just saying I prefer a single battery mod.