If considering the Arundel SideLoader, be sure to shop carefully, as they also offer the OtherSideLoader rather than make a flippable/changeable product. If stoker is using it, stoker should have final say in which side loads. Remember (and possibly remind her) that the timing chain has no derailleur, and can therefore slice off fingers.
I think my wife/stoker has requested the OSL for both of her (forward-facing) positions on our daVinci. Alas, I have not purchased these yet.