My standard set-up is joytech 510 2.5 ohm atties at 4.5 volts on my provari and has been for the last 10 months. My situation is reverse of yours. I've tried the dual coil atties from clouds of vapor, but want to try the 306's and have one being delivered today from litecigusa--forgot to get a drip tip, so I'll have to wait to try it.
I don't know what pv you are using, but on the provari dc atties cut my battery time in 1/2 using AW IMR high drain
batteries. These dc atties--the only one's available at the time--were low resistance 1.5 ohms; they don't play well with high drain
batteries. On the positive side, they really brought out the flavor in my juices...vapor production was pretty close to the same as my 510's (ymmv). I may revisit them when I can get 2.5ohm or better. I def recommend everyone give them a try.
I'm interested to see how the 306's do when it comes to the flavor production and vapor--I've heard good things. However, if I am not overly impressed, I'm happy to continue with my current set-up.
cheers,