they probably have interlocking gears so colapsing when the nut is tight would be impossible. I guess an advantage might be that you can choose the pick angle that best suites you. However, there is likely only one good angle for every tool geometry.
In my experience, Omega Pacific doesn't usualy make very good stuff.
The only company that I have found to date to produce affordable and at the same time quality equipment is DMM. Some, not all.
And plus... you can get quarks for $75 more with leashes.
check out these sites too
http://www.lacordee.com
http://www.mountainmagic.com
both are canadian.