Thanks for the precious input.......The watts would be a big thing, but also..
Form factor - the radius is quite a bit shorter, think shaving the size of a half a subtank off...
I haven't compared the weight but i am guessing its lighter?
Radius little bit cheaper than p3 plus 18650 cap
The p3 does give you more choices with batteries
The radius can drive a sub ohm coil very well should you ever want to try that
Just some thoughtsboth will make you very happy i am sure! I love all my provaris