There are a number of videos out there comparing these two drones. In this one:
SKSVideoGuy makes an interesting point about the obstacle avoidance proximity sensors. The P4P has sensors all around while the H+ only has forward facing sensors, and in the case of the RealSense versions, downward sensors. While that may seem like a disadvantage, he points out that since the P4P camera can only face forward, to get slider and backward facing shots, the whole drone must turn and fly that way. Whereas the H+, with it's 360-deg camera and retractable landing gear, can get all these shots while flying forward. Hence, only forward facing sensors are required.
SKSVideoGuy makes an interesting point about the obstacle avoidance proximity sensors. The P4P has sensors all around while the H+ only has forward facing sensors, and in the case of the RealSense versions, downward sensors. While that may seem like a disadvantage, he points out that since the P4P camera can only face forward, to get slider and backward facing shots, the whole drone must turn and fly that way. Whereas the H+, with it's 360-deg camera and retractable landing gear, can get all these shots while flying forward. Hence, only forward facing sensors are required.