Re: rock river LAR-15
my M&P has a crappy, heavy trigger pull.
RRA has a very nice, crisp, short trigger pull.
both are removable carry handles, iron sights, plastic hand guard, normal el-cheapo adjustable stocks.
both are "M4" variants, adjustable stocks, flash suppressor, 16" barrell.
the RRA is a tad heavier (beefier barrel, internals?).
the feed ramp on the RRA is chromed and way beefier than my M&P (if that makes sense)
the RRA has the houge grip
my M&P ha the crappy plastic grip
feb 2010, M&P $900 (happy 30th b-day to me!)
Nov 2012, RRA $1150