. . . I have heard reports that large sound pressure levels can make the unit a bit dodgey. . . . I would recommend going P2 all the way. FS are good when you have a chance to reshoot stuff if the unit has a moment. P2 is rock solid.
I agree that P2 is solid. Our few experiences (rent before buying) were bad experiences. One the FS100 lost the camera just before shoot time and on that camera we lost all the footage and of course it was the MAIN camera not the B roll side AND another was a wrong setting on the FS100 and we ended up recording a codec format that was on the menu which NOT EVEN Firestore supports (thanks Edius for bailing us out on that one) AND a dying battery during the shoot that we didn't have a clue was happening . . . and thus . . . 3 for 3 was enough for us to say . . seek another solution . . P2 - YES !!