I have a RRA Flat Top 16 inch, but after two years of shooting it, I think I would get the same rifle but with 18 SPR barrel and 1and 7 twist, this is the most versatile setup IMHO, you can do CQB and Long Range work with the right optics setup.
Put a nice scope on it 3x9 or 3x12 by 40 and also put a little red dot on it for CQB work mounted on a 45 degree mount from Yankee Hill Machine or get the mount that puts it on the scope. This has you covered from 0 to 700 yards. All you have to do is change ammo, for close range use the xm193 for long distance use 77 grain Black Hills Load.
The best part of this setup is range days. Shoot some quick 25 yard stuff, then shoot some 300 yard stuff and be more accurate than the bolt action guys who havent improved their rifles.