Rex has always seemed like a perfect fit for the Patriots. With the money they gave him, they clearly have big plans for him and not just for special teams (though that's become his calling card).
Excited to see what he brings to the table for them. It's interesting, they do already have two pass/scat backs in Dion Lewis and James White, both in the last year of their contracts. They had a reliable ST player in Branden Bolden (now a free agent). Burkhead comes in on another 1 year deal, and it's a $3.15M deal with $1.1M in signing bonus and $1.8M in base salary.
For reference, LeGarrette Blount signed an incentive-laden 1 year deal with a $100k signing bonus and $760k base salary last April. The max incentives brought him to c. $2M, I believe. Then again, the Pats seem to be spending somewhat uncharacteristically this free agency.