So I'm eyeing up the £319 backpack for my P4 and wondering if there are multiple versions available, one for P1 - P3, and an updated one for P4. The cause of my quandary is that while it's also available from other retailers (such as Wheelspin Models for £315) the DJI store is the only one which mentions the P4, and even shows a photo of one in-situ. Jessops meanwhile sell an apparently identical product for £250, which they claim is for P1 - P3 but then go on to saying it's compatible with any Phantom. I find this odd. If it's just a case (hah!) of their product description being out of date, then why are they so much cheaper than everybody else?