The RX is usally the prefix used for the non-turbo 2.5 litre models. The RX L series was the last turbo with the RX prefix, that was back in the late '80s.
I don't know anyone who's ever taken one off road - their approach and departure angles are very poor for an offroad vehicle.
Actually a mate took his up the back paddock one year, not really "offroad" as most know it to mean.
Cheers
Bennie