The DLOC pic rail conversion is mandatory for a Harris. The sling stud thing was great in 1998, but the ability to use a pic rail with qd is so nice and rigid.
Disclaimer, never used an atlas. Like my Harris.
I really don't like QD adapters for the Harris because they add height and at the end of the day the stud mount is still used, just the bipod is mounted to the stud on the adapter and adds a fair amount of height. I like the one you posted, that one makes sense and is really what Harris should be using in 2018. I am converting to a KRG direct spigot adapter that has a similar design, just doesn't detach quickly or mount on a rail. I don't move it from rifle to rifle though