Glock 21sf Gen 3 with Picatinny Rail

I have one of the Glock 21's that has the ambi mag release and full picatinny rail instead of the normal Glock rail.

My understanding was that they made it to fill/go after a govt agency contract but ended up having problems with the mag release spring. I know Glock will swap frames with a standard gen 3 frame at no charge, but I'm planning on holding on to it as a prospective collectors' item.

Anyone have more info than above on them? And any insight on to the viability of them being a sought after collectors' item?

thanks!

I have one with modifications. I dont know about collectible-ity

I dont know of production numbers. Try calling Glock or sending an email

Several topics online of the magazine release not locking or releasing. I bought replacement parts and spares. Installed them. No problems but good peace of mind. Very simple to do there is a youtube video.

I forget but there is a certain generation mag that will not latch.

I will update