I did a test video for a project that I plan to do for an ice hockey team using a Phantom 4 Pro and a DSLR on a Ronin M.
The P4p is very stable indoor with no GPS and the VPS system worked without any issue even on the highly reflective ice surface. The biggest challenge was shooting over the goal where the distance between the drone and the safety net was quite small.... and the net is black so you almost don't see it. I didn’t expect the drone to fly so well indoor and over the ice.
I do photos and videos for the professional ice hockey team so I get a couple of times a year on strange hours the rink for me to test and try things out. I wish I could do it more often nevertheless definitely cool.