I own a P3 and if the power (Max 40 watts) fits your profile and the price your paying, it's a fine mod. And it's built like a Sherman tank with outstanding CS and repairs.
HOWEVER, you need to be aware of a few gotchas which are my own views.
1. Beta firmware: Their is nothing "rare" about this Beta. Matter of fact, most have upgraded the firmware. I don't see this Beta ads any value but rather detracts from the resale and enhances the opportunity for glitches.
2. Firmware is up to V39.
See this page. This Beta is probably V35 or V36 as I recall.
3. The Firmware is NOT user upgradeable. NOT! You either send it back to ProVape or find a B&M that has the proprietary hardware to upgrade your firmware.
I sure don't wish to sound like a ProVape basher. The critical factor is how much are you paying? And of course your desire to upgrade the firmware. The vape that the P3 delivers is just as smooth as the Radius and includes "Boost" although the menu system on the P3 is not as easy to navigate as the Radius.
Good luck