The second two, I have a sneaky feeling that they're plated common chambers. I'd avoid them until I knew for sure.
The first one is not a Nargilem knockoff. From what I understand, they're the same thing. They just slap a different brand name on them. That said, they're decent rigs. I have one. In fact, if you decide on the PN Nargile, you'll save alot of money by shopping closer to home.
It's amazing you much less you pay without a brand name.
PN Nargile 630 - 59,90€ = $89.17 vs $64.95
PN Nargile 480 - 39,90€ = $59.33 vs $44.95