I am just looking for the best priced Grp III Synthetic oil. I have run M1, Amsoil and GC in the past in my Toyota 4.0L V-6. I have had great UOA so far. But I am the froogle type and I do like cheap oil. My 32 cent Pennz Plat. is the next oil on deck for this vehicle. Off the top of my head , Motorcraft even though its a blend its grp III right? Any other suggestions? Amsoil XL series?