Good question!
I’d have to put this to the test, but I’ve definitely used ProRes for playback in the past, and now almost all of my travel VJ clips are in H.264 on a small SSD drive (make sure the H.264 clips have a keyframe for every frame, otherwise it gets messy).
Based on the old benchmarks from the HAP site:
https://hap.video/benchmarks.html#:~:text=While%20H.,and%20larger%20ultra-HD%20resolutions.
Under the performance chart:
It has HAP playing 14 4K30 clips while ProRes (on that system) Maxed out at 3.
The last time I ran a HAP / VDMX playback test on an M1 Max 32GB MBP, it played back 107 1080p30 videos at the same time. I’ve been meaning to do an 8K test, but in theory, this M1 MAX should hand 26 4K30 HAP clips. Estimate 12-13 8K30 HAP
I know the M1s have a Prores “chip” I’d like to benchmark. But even going off the old stats, from above, that at least 6 simeltanous 4K30 ProRes clips. I typically don’t exceed 2-4 simeltanous clips while performing.
The issue with playback of these larger codecs ProRes / HAP, comes down to drive / SSD bandwidth. When I did the test with 107 1080p30 HAP clips, most of them were stored on the built in SSD with R/W speeds somewhere around 3,000-4,000 MB/s, a lot of external SSD’s claim a max of 1,000 MB/s. I think a few newer ones claim 2,000 MB/s. But if you’re storing them on an external hard drive < 200 MB/s you might experience playback issues no matter what machine you’re on.
All that said, I’d try it. If you have already exported your clips out of FCPX as ProRes, if they work, they work! But if you hit some playback bottlenecks down the road, try to convert a few to HAP (or upgrade your external SSD) and see if that helps fix things.
I know the code for VDMX and HAP is still being updated, so I wouldn’t be surprised if there’s a new version of both in a few months that toss these benchmarks out the window.