Im just throwing out my personal opinion. Factoring in the above comment, I would not get the PS90.
I say this for a few reasons. First, I like the idea of something unique to pass down, the problem I see is eventually FN may stop making gun in 5.7 which will lead to really hard and expensive ammo.
The ammo is a second reason, the style and operation of the ps90 is super cool, but it is a very expensive rifle with very expensive ammo, and we can’t get the good stuff that really makes the round shine. If you don’t mind putting the money in to train with expensive ammo then it could be a useful gun. If it’s a range toy there are other options I personally think still fit your want/need for example:
Tavor or Aug- not a typical AR, unique looking, common ammo, the Tavor is offered in 9mm (I shot one, it is fucking awesome).
RMR-30 or whatever the rifle version is called- Similar to the PS90 in the small fast round, good capacity, cheaper and easier to find ammo, cheaper purchase price if the gun.
MP-5 clone- while not modern, it is a cool recognizable gun, you like German stuff, you already stock 9mm. You can build it as a pistol with a brace to avoid having to do a tax stamp on it.
UZI- well, I just think they are cool
The PS90 is cool, stupid looking if you don’t SBR it though. But to me it is way too expensive for a range toy and ammo costs too much to train with it for a defensive gun. I know you have a .22 can. Is it rated for 5.7? If so, you would be silly to not make it a SBR and suppress it.
By all means, do what you want but as much as I like the PS90 it is too expensive for a novelty in my mind.
I want to shoot either one you get though
