As to the Jard, you'd have to call them and ask the difference. They have a website and I have talked to them...
IMHO the quality of the pull is excellent; perhaps the more expensive ones could be better--but if so it would be wasted on me. All I know is that I wish all my weapons had pulls as good.
I opted for the non-adjustable in pursuit of the KISS principle. It can't un-adjust.

