They seem to work ok. I run with the Chiefs, and Davis spells Charles well. Also don't see any players disappear. As far as injuries go... I love it at 70. I see alot of nagging injuries thru out the game, where players may be out for a few plays, and I may lose some for a week, or longer. That is the gamble you play. NFL teams in real life have to deal with that every week. I love having to gameplan according to my inactives.
CFM... I never play "Play Now"