Best Engine oil for Toyota Prius

I use Mobil1 full synthetic 0w-20 advance fuel economy oil. As long as you get oil that meets the manufactures's spec, you will be fine.

I use castrol magnatec beucase it has some kindof ionization tech where it sticks to metal surfaces to reduce start up wear which the prius is constanly starting/stopping.

I've been using motuls hybrid oil that's specifically for hybrid cars on my gen 3 prius. Gave me +2mpg onto of what I do and "nicer" ride

I found out that I have a really low level on the dipstick. Luckily I had a bit of Kixx 5w30 from another car lying around so I added a few cups which brought me over the minimum. Since then - no warnings!