AJ is too good and too consistent year to year to ever bench in Roto. If you are playing H2h he is not an ideal player to say the least, but in Roto he is money over the long haul and basically should never be benched. This is not the type of player you should be messing with day to day. You should really never mess with your top players and leave them in there all the time and unles syou play in a very shallow league, AJ should be starting every day.
You want a guy that falls into this category and is a killer...Durazo. What a waste of food. He is barely fantasy worthy in mixed leagues which means he is often bench material or platoon material to start with. You play him he hits nothing. Others are guys like Ibanez, Koskie and Sanders. It is not the studs that kill you, it is the marginal guys you play as fill-ins or to sub for hurt guys.