Viking MK2 Sling - points in mounting?

[m4brian]

I've set up my sling almost like the instructional video on the BCM web-site. (using CTR with swivel in rear instead of slot in stock).

But, is it better to use a sling mount FURTHER fwd on the rail, rather than my built-in DD rail mount (I have the 12.0 FSP)?

It looks like it may be easier to carry the rifle over the back muzzle up, and switch to leftie shooting (I'm right handed). True?

Thanks.