[Note that 0w20 isn't the world-wide specification by TOYOTA. Go by the grade your Owner's Manual says.] I thought Redline was for use in high-stress situations, eg turbo or an engine which uses oil. PRIUS has a relatively low-stressed Atkinson Cycle engine - I wouldn't be spending extra on a specialty oil for it.
correct engine oils are formulated to solve a problem that the engine will undergo. it's good to know you care about your car enough to look into these things. However, if you want just change your motor oil and transmission oil a bit more frequently then. instead of doing 1 or 2 a year, do 2 or 3 a year. just add one more interval. Posted via the PriusChat mobile app.
You are right I thought I should of used 0w20 but in the UK it is 0w16 according to Toyota, it will have to wait until next service now