If your looking for built-in protection circuitry both DNA and RDNA as well as the sx330 chip far exceed the P3 in performance and adaptability.
20 watts for 250.00 seriously ? I thought the RDNA 40 was bad.....
Looking at a Provari in terms of a watt per dollar ratio is an interesting concept. One that completely misses most of the point of a Provari, but an interesting one none the less.
As others have mentioned, there are much more powerful devices out there for a lot less money.
Some advantages to buying a Provari would be build quality, warranty, accuracy, safety and after sales service. I have one, I don't use it much, but I am glad I bought it.
Some disadvantages are price point (for some) and lack of power if you want more than 20 watts.
So only you can make the decision if the Provari is right for you.
As a first mod I would actually say probably not. What happens if you spend $250 on it and dislike vaping? Maybe follow some of the advice on this thread and look at another set up until you are sure you like vaping, then do a little more research and comparisons and then make a decision.
Finally I'll say that few who buy a Provari regret the purchase. Those that do are able to resell it for about 95% of its value so the risk is low.