Good quality but somewhat pointless - Leupold Integral Ring Insert Mark 4 IMS

i bought the insert in a hurry first thinking that it mounted directly to a 1913 rail so my mistake. i ordered the separate base and all's well however i really don't see the point in a base that accepts different inserts when you have to remove it to switch inserts. if you are going to mount a rifle scope on an ar why not use a good quality one piece ringset and buy another base for any other optic you plan on using. leupold quality is never an issue, im just not sure that this design is very practical.