I have several suggestions.
I currently have Joyetech 1000mah (3.4 volts), Smoktech e-Power 14650 (3.7 volts), and a Smoktek Woo (5 volts).
I would have said that "one of my PV's is an eGo-T", but I think it's absurd to link a battery/power unit to any particular atty/tank setup, whether it's a Joyetech -T, -C, or -XYZ. It's a 3.4v power unit that happened to come with a one-piece atomizer and some 1-ish ml tanks. You can obviously put a wide variety of attachments on it.
You're not going to get the hard hits you want from that power unit. You can get OK ones with a 1.5 carto, either in a tank or not - (I love the Smoktech 3.5ml DCT, just don't use a Smoktech carto in it - they're just gone to crap - bad filler material), or with a drip atty (306's are great because you can squeeze-fill them right out of a bottle for easy tasting of multiple flavors, and optimum saturation of the coils regardless of flavor); but at 3.4 volts, you're only going to be getting 7.7 watts even with a 1.5 LR atty. (Watts = volts x volts / resistance in ohms). Most juices really come alive at higher wattages, like 9-12 IMO.
With a 1.25 carto you could get 9.2 watts, just on what I would call the low end of the enjoyment scale. [So: "Is a LR cart the same as VV though?" Kinda/sorta/with certain juices maybe]. Short-term, and for the least amount of money, you could get some XL stainless steel cartos and a 3.5ml Smoktech DCT (tank), with the latter optional. That tanks works best with stainless steel cartos that A) have a flange on them so the tank won't slip down, and B) are slotted per PBusardo's instructions. You'd need a cheapo Dremel clone with a thin (1mm thick) abrasive cutoff wheel and arbor, but then you'd be getting great hits for hours on end. Hits like you've never had before, ever, even at 3.4 volts.
If you just get the 1.25 ohm cartos (1.5's in a pinch), fill them like this: put in about 10 drops, wait a minute, repeat about 3-4 times until juice just begins to drip out of the battery end, wipe the end off, screw the carto on, wipe where the battery and carto join, put drip tip on, and then enjoy what will probably be the best hit you've had yet in your entire vaping life.
If you do get the tank, you can have about 300 such hits in a row before you have to add more juice.
Obviously, variable voltage is the way to go, and if you can swing it at all, you can just avoid a lot of interim expense and postponed enjoyment by getting a ProVari V2 and some 2.5 cartos which would put you right around 8 watts at 4.5 volts, which is right in the middle of the ProVari's 3.0 - 6.0 volt range. You could also get 3.0's or 3.5's as well just to play around with. Let's see: 6v x 6v / 2.5 = 14.4 watts; yeah, that's enough to crackle any juice under the sun. 6v x 6v / 3.0 = 12 watts; still plenty high, but you sound like you want to be able to create insane amounts of vapor and TH at will, so I'd go with the 2.5's for sure as one of your choices. [Edit: 2.0 ohms puts you right at 10 watts at 4.5V - not a bad way to go either].
Other course of action: get a Smoktech Woo, but order protected batteries at the same time. They come with unprotected batts, which isn't cool. I'd get these bad boys right here:
UltraFire 880 mAh Protected Rechargeable Battery RCR123a Compatible
I'm using my Woo as we speak, and it's my best vaping experience so far, without a doubt. Right now it's putting out 5.67 volts; my "studio reference" flavor, Geoff's Blend from Tasty Vapor, at (5.67 x 5.67 / 2.5 =) 12.8 watts .... wow. Sweetness on my tongue that I never tasted before, huge clouds of vapor, nice TH at about 12mg ... yum.
I still have a warm place in my heart for the Joyetech tanks, and I'm going to get a -C setup with LR attys that I'm sure I'll use a fair amount, just for the convenience, and to let people try different flavors relatively easily. I'm working with about 20 people right now who want to get off of stinkies, and the easier it is to let them experience all of the different setups and flavors the better.
So that's it - you have lots of ways to instantly improve your vape, from the super-cheap and satifactory to the not as cheap but super-excellent. If you're going to keep vaping, which I suspect you are, I can't encoutrage you enough to just go ahead and get yourself a ProVari and be done with it. Even with my Woo, I long for the ability to power a particular juice in a particular attachment at a particular wattage, and it's hit-and-miss and quite a hassle, with all the combinations of juices and cartos/tanks I have. With a VV, I could have a perfect vape regardless of flavor of juice, nic level, PG/VG ratio, or what attachment the juice happens to be in.
In conclusion: ProVari V2. Do it, do it, do it.
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Must mention: The Darwin lets you choose a wattage level, and automatically detects the resistance of the atty that's attached to it and delivers the needed voltage. How slick is that? Downsides: it's a little clunky-looking (certainly not a tube), and the battery, while apparently heroic in lifespan and capacity, isn't replaceable. I'm looking for a mod that does what the Darwin does but uses replaceable batteries. Don't really care what it looks like, as long as it's well-designed and built. Anyone?
As far a flavors go, I have tried a flavor called Desert Joe from Smokeless Image that tastes very close to a traditional cig. Just a thought. Good luck!
