So, anybody have experience with or own one of these(and not on COD/Black Ops)?:
https://www.gunbroker.com/item/787493540

Mother of God..?...

Dont have any experience but

I've only fondled what I think was a real one for a little bit. It seemed very light and toyish. Didn't have any dummy rounds to cycle through it or anything.

they are cool, but the main problem is that they were never really meant for use with chalk rounds, so you can have a launcher full of loose chalk if you aren't careful. There are very few originals out there, but a group built a number of reproductions, some of them having problems with heat treating on the internal parts, but many had those parts treated afterward or replaced with proper parts.

Ask on subguns or maybe grogs forum

autoweapons.com has had some for sale for a bit, not sure how their price compares as they don't like to advertise prices anymore.

If you need more info, you can get ahold of Kevin Dockery, he knows a bit about them and likes to talk. Pretty nice guy
you can see him in this video, and he also watches subguns occasionally.  https://www.youtube.com/watch?v=aMQ1VVvjO0l

if that doesn't work, search china lake 40mm on youtube for the weaponology segment on it

I just handled one at SAR, didn't get to rack it or anything.  Seemed high quality, but damn $17k...  You would need to have a serious boner about 40mm or already own one of nearly every transferrable available to buy one...