I've posted some details on MA J (probably in the other airlines forum about a year ago). It is a below-EI standard J, but also priced low (typically 30% of AA J price). In fact often cheaper than BA WTP, so think of it as a super WTP service. Bit of a waste on an OWE ticket, though. Food/drink is good, crew try hard, and operations are surprisingly reliable given the MA fleet of 767s is 2, soon to be 3, aircraft. MA has always offered big incentives of various kinds to fly them TATL in J (it probably is the fastest way to Emerald, for example, but by invitation only so you cannot game them).