Has any one been to a DJI sponsord new piolt experience?
Is it worth going to if you already have a p3p or is it just for people looking to buy one?

I went to one in LA. It was only okay as they couldn't actually fly them (last minute venue change). So it was a show and tell for new buyers mostly. It was, however, VERY handy to have direct access to people in the know. If you have any question, they can answer it right there. And if you're having an issue they'll give you their direct email address to help you resolve it. As far as information goes, they are well aware that their customer service is...lacking to be kind. They just leased a new customer area with I think 10x the space they currently have and are working to make it better. But I did get a DJI hat!

I went to one in San Diego.  It was mostly for people looking for some hands-on experience flying them before buying.  But if it's not too inconvenient of a location, it might be worth getting a chance to meet the dealer face-to-face and start building that relationship.