edit: I’ve opened a feature request for this, as that seems to be the best chance that this might get improved (if at all possible).
I’ve also finally gotten my hands on my PPM, overall I’m very happy, but the Miracast implementation does indeed seem very limited. I wonder if that’s a software or hardware issue.
Standard of comparison
I’m mostly comparing to the Microsoft Wireless Display dongle (I think version 2), which is what I have used so far with my current/previous connector (and which I also use for presentations etc. in professional/education settings).
I also used to use a cheap Chinese Miracast dongle in the past, which occasionally lost connection, showed artifacts and often had issues keeping video and audio synched. I don’t recall specifics about the input lag (I think it’s been about two years since I last used this).
Android - Miracast experience on PPM
It seems to be good enough for showing pictures and videos from an Android device. There is a noticable delay in response (in swiping through pictures/videos in the Gallery it seemed to be about 2 seconds), but video playback itself seems to be fine. I didn’t particularly check for picture quality and didn’t try out a lot, but it seemed to be decent.
I suspect given the input lag Android gaming via the cast functionality might not be feasible, but I haven’t tried this (yet?).
Considering the issues encountered with Windows casting (see below), I’m not actually sure which resolution the miracasted image uses with Android (not sure if there’s a clear way of testing that).
Limitations of Miracast experience in Windows
I had no trouble finding and connecting to the projector from my Windows installation (you need to go to the Miracast app on the PPM first, of course).
However, the input lag makes navigation very unpleasant if you’re intending to actually operate on the projected screen. I haven’t measured it in detail (not sure what the technically most sound way would be), but what I reported above for Android seems plausible, i.e. about 2 seconds delay. Which makes using a mouse quite taxing for your brain.
This completely rules out using the integrated miracast for any kind of serious use apart from displaying more or less static content (possibly video casting, but you can normally do that from the device itself), so presentations might be ok, but you can forget about doing anything interactive unless you are very very patient with your input methods.
Thanks to the integrated capabilities I won’t need to project to the device for most/all video content, but one of my use cases with the MS Wireless Display is to occasionally play games from my PC on a large screen. Obviously nothing competitive FPS players would do (I actually haven’t tried playing something like Counterstrike this way), but we’ve played games like Hellblade: Senua’s Sacrifice or A Way Out this way without a distracting input delay - I’m sure there’s more delay than with a direct HDMI-cable connection, but I never found it noticable or distracting.
On the PPM, I haven’t tried this yet, and I think unless there are siginificant improvements I won’t because the input delay is immediately noticable just by moving the mouse. This means that I can’t even imagine using this setup for round-based games (whyever one might want to play them on a huge screen) because you’d get mad trying to move the mouse and then wait and see if you moved to the intended button.
The second major issue is the resolution. As mentioned above, for some reason the max resolution I can get on windows via Miracast is 1366x768, so no FullHD (this is what made me a bit suspicious if even when casting from Android you actually get a fullHD resolution). Again, not sure if this is a limitation due to limited bandwith on the hardware side or some software limit.
Due to these limitations I haven’t further tested the qualitiy of the casting for artifacts etc.
So for me the Miracast feature is fairly useless as it stands, at least for Windows. Luckily, I have my Wireless Display dongle, which gives me FullHD resolution and hardly any noticable input lag (and just the occasional visual glitch). It is a shame however to have a device that could offer an all-in-one package doing so much worse than a dongle from 2016. If the limitations could be alleviated in software, I’d very much appreciate it.