3 identical guns but different brands?

So basically I'm just wondering what's the actual difference between the artemis cr600w and the smk cr600w, they're just exactly the same to me. 

I want to add to this equation the diana trail scout, sure it has a synthetic stock but the only other difference in it is that it uses two co2 cartridges rather than one co2 cartridge like the previous two. Are they produced in the same factory or something? 
 
Depends on what country it's marketed through as well.

Nothing new see Beeman R9 HW95 or Beeman R7 HW30s or R11 HW98 or Rx2 HW90 and so on.

Then you got Diana Skyhawk nicer stock than the P15 etc... Funny the $300 - $350 P15 seemed less of a lottery than the Diana labeled version...

Air Venturi Avenger-DAR Gen1-ATI Nova Liberty etc... some variations coming from the same Chinese factory...

I paid $219 and $199 for my new ATI Nova Liberties (wood and synthetic) plus $60 shipping for 4 of them a couple years ago direct from ATI.