Peters leads all players with 19 interceptions since 2015, and his passer rating allowed has remained at an astonishingly low level during that span. (Peters' passer ratings allowed from 2015-17, according to Pro Football Focus: 67.1, 65.6 and 66.0.) Not to mention, he has discouraged quarterbacks from throwing the ball in his direction, due to his remarkable ball-hawking skills on the perimeter (targets have dropped from 151 to 91 to 72 each year)
he's arguably a Top 5 corner.....no doubt Top 10
http://www.nfl.com/news/story/0ap3000000917349/article/patriots-qb-succession-plan-marcus-peters-trade-assessment
he's under team control for 2 seasons (if they exercise his option and way below franchise tag level)
cap hit 2017 : $1.7 mil
cap hit 2018 : $9.5 mil
http://www.spotrac.com/nfl/los-angeles-rams/marcus-peters-16742/