Not much interest?
I have one and I like it a lot. There is a lot to like. 20 round mags run a few bucks at gun shows and maybe 5 for brand new ones. Takedown is two pins and the whole thing is open. It is a very different action from the AR. It is said to be blowback operated, but the clever designer uses gas to assure the brass kicks out. It is a machine gun action with a semi-auto trigger and is happy with high rates of fire. It is battle field accurate, meaning center mass as far as you can see. When I got mine I could find original G3 accessories, such as the clamp mount and BDC scope. Good glass in old German optics. There is a a ptr model that comes with a pic rail welded on. And there is a rail that clamps to the receiver's clamping points.
Everything that fits the G3 and the semi-auto version fits the pt91 too. It's as reliable as a drum/magazine fed firearm can be, and plenty accurate for most hunting chores. Plus it's something of a workout to hump around, good for we elders as a workout device. I figure it's appropriate for the outdoors because, in spite of being a small-bore arm, 21 rounds in a second or two should disconnect most bears and 'hadis in a second or two . . .
It handles M80 ball and .308 hunting loads with equal ease, and I've read that it handles lead ammo equally well, and possibly reduced loads in case someone wants AAC blackout performance from their main battle rifle.
Sometimes it can feel heavy, but I judge that to be an indication of my physical condition rather than the gun's fault. And tricked out .308 ARs aren't so lightweight either.
And with the paratroop collapsing butt wire stock the 90 is quite compact, about the size of AR pistols, but with the longer barrels for longer range.
I haven't actually shot mine in a while because the poop has not yet reached the rotor . . . but it is a lot of fun to shoot with what I guage as soft recoil. I say this from side-by-side comparison to the Savage 99 in .308, which has attention getting recoil, as the Savage is miffed at my interest in my 21-chucker Model 91. Harrumph.
