We've had the Rav-4 (petrol),CRV diesel and X trail. The CRV diesel was the most refined, Rav-4 nicest to drive, and X-trail most accomplished off road.
All 3 were typical Jap plastic fantastic inside, and all 3 were bought with engine problems, the 2.2 cdti in the CRV can suffer from oil pump issues where the little chain will snap and take the bottom end with it. The X-trail had issues with cam chain guides which knackered the chain itself,The Rav-4 2.0 VVTI is the least likely to grenade itself but ours had a problem with the HG. So basically its best to go and check the cars, check the history, check the regularity of oil changes, basic stuff really.