I know this is not exactly your question...
One major obstacle for most (as far as upgrading to any of the new iPads) is the elimination of the headphone jack. That is a HUGE loss as almost all Bluetooth headsets and speakers have latency. And that delay throws everything off. So if you are using a lot of sound/music in your vidz (especially is editing "on the beat"), this is something to consider.
Not a big issue, as you just buy the adapter and then can attach your headphones to the Ipad Pro.
I did not communicate clearly:
The adapter has latency. By the time the signal is processed, there is a slight, but annoying delay.
There was a Kickstarter of a device that boasted zero latency to fix this issue... but it never got funded.
I am currently frustrated by this latency problem using my Zoom H6 recorder and Filmic Pro. As soon as the "handshake" happens, there is a slight delay (and echo). I have gone back and forth with Filmic about this. But in the end, the delay is still there. So I am forced to record without a live monitor (i.e. my headphones).
Oh, wow, i did not know this. I have the same adapter that im using on my new Ipad Pro 2018, but cant say i have noticed any delays. But I will try and listen more carefully for any delays next time.