I have the Nikon mount for my M-223; I also have a LaRue mount on another scope on another rifle.
IMO, unless you want the quick detach capability of the LaRue SPR mount (the corresponding LaRue mount to the mount that came with my Nikon is the LT104 for $210), there's no need to toss the Nikon mount for one that costs you another couple hundred and then some. The LaRue is certainly a nice mount and better in some ways, but quite honestly, a scope mount is to hold the scope without letting it shift and lose zero. The Nikon mount appears to be plenty good at this. It may not be able to be removed and replaced without losing zero like the LaRue mount (never tried it with the Nikon), but unless you absolutely need that feature I see no need to swap out the Nikon mount.
And as said, unless you're going for very long range shooting, you don't need the 20 MOA mount. If you're going to zero at 100 yards or so the regular mount will be plenty good enough.