I've been playing with my Play For Dream MR headset for a few hours, here are my thoughts on it : the passthrough is at its best in excellent natural lighting (no real surprise there), but this takes it to just being a notch better than the Q3 passthrough imo, it's still close though, I'd say PFD MR is 7.5/8 whereas Q3 MR is 7, and in lower lighting levels there is slightly more noise to the PFD's MR image compared to the Q3's.
Head position is absolutely crucial, to the unaware first impressions with this headset are probably going to be bad, but with better eye positioning which for me is no facial interface and a Studioform top strap the image is excellent, the lenses are very good but not as good as Q3, Q3 lenses are 9.5/10 whereas these *when eye position is optimal* are 8, I don't see much glare in the notoriously bad for glare boot up screen, but of course it's not secure on my head like this so a better solution is needed.
The controller tracking is good but there is a slightly annoying blind spot which the Q3 doesn't have, it's when I stand with my arms just hanging down straight at my side, it doesn't track for me then. Battery life is poor, probably around the same or a bit less than Q3. Sound is ok, not great quality, might be a little bit louder than Q3. Software, it's functional, quite basic, not as intuitive as Meta's OS imo or maybe being used to Meta is the factor.
I've yet to properly tinker with PCVR gaming (briefly tried Beam.NG in Godlike with VD, looked very similar to my Q3 image, certainly no worse), I think I might save PCVR stuff until when the forthcoming Monster mode comes out. I have been able to get my own little Meta Quest MR app (TykeAI) running on it fine, it looks better than it running on the Q3 for sure. I'm slowly coming to a similar conclusion to what Seb of MRTV stated about this headset, it's not $1500 better than a Q3 but it is better, and might be suitable if you really want that bit extra and have the spare cash.