I know 2 people who have a V3 and love it, although have said at times it performs a little too well.
If you get a high voltage device (V3) don't use LR atty, you will fry it. I have the Icon (3.7 volt device) from PureSmoker and could not be happier. The 2 LR attys I have found to be the best are the LR 510 from ELiquidPlanet.com, and believe it or not EastMall ( to be fair I've only tried 2 of theirs because they have lasted so long). As previously mentioned while dripping, only drip 3 drops, maaaaybe 4 but that's it. That should last you about 5-8 healthy draws. I started with carts (as most I imagine) and found that I have to drip no more often than 'topping off' a cart. I say topping off because while a cart may hold more juice, it has been my experience that the majority of it hides in the tip anyway, and is never used.
Not sure if you are open to the 3.7 volt thing, but I have found a 3.7 device, and LR atty is the best balance. Dripping in my opinion is much, much better than a cart. Good luck and I hope some of what I said helps.
Oh yeh, if you decide to drip, do yourself a favor and spend a few extra bucks on a decent tip, preferably wide mouth. A finally broke down and spent the extra 2 whole bucks on a wide mouth delrin from Super T Manufacturing, and it is soooo worth it.