Redi-Mag?

So of the two models here which is best and are they practical to get? Not sure of the difference here.

http://jabtac.com/store/index.php?main_page=product_info&cPath=9_13_51&products_id=339

http://jabtac.com/store/index.php?main_page=product_info&cPath=9_13_51&products_id=340

Quick attach. Easier to install and remove but just as secure.

This.