I've recently taken a greater hand in maintaining sweetie's Prius. The oil that we put in at the last change (SuperTech 5w30 Full Synthetic) is, fine for the situation. However, at least in the Prius, it is so clear that literally cannot read the dipstick. I'd like to find a good syn, 5w30, that has a bit more color to it. The M1 that I run in the Camry seems to be a little darker, but I'd like some suggestions on what else might work.