In my previous Toyota that took T-IV - I used only OEM Toyota ATF - too many horror stories with incompatibility with Toyota Type T-IV. Still have some leftover OEM fluid that I have to use up somehow.
My 8th gen Corolla was spec'd for Dexron II/III ATF - so it sees either Redline synthetic ATF or Valvoline MaxLife DEX/MERC ATF, though the Corolla really does run better with Redline ATF, Valvoline is much easier / cheaper to stock up on.
In my current Toyotas that run the newer WS - I'm running Valvoline MaxLife DEX/MERC ATF. Seems to run OK with the Rav4 (did a complete flush with it) - the Matrix is actually having trouble with it for some reason. Will probably run Toyota WS in the Matrix during the next oil change interval.
Even though the factory WS fill is considered "lifetime" - I still flushed them out. The first 10K miles, the fluid turned to a nasty shade of brown in the Rav4 - immediately flushed it out and replaced with Valvoline, the car drove nicely with the new fluid. Smooth shifting, no slipping, unchanged MPG - so far, 40K miles on this change, so far so good. The Matrix, had a bit more miles on it before I got around to changed it (~30K) as it wasn't as badly discolored as the Rav4 - did the same thing, full flush with MaxLife ATF - but here, the car hates it. Shifts are noticeably more aggressive, lots of transaxle whine - mileage dropped a bit. Going to drop the pan and see if there is any damage.
That said, lots of people seem to like Valvoline MaxLife DEX/MERC ATF. Though there is a growing number of Ford and GM owners are having issues with it.
Formulation of MaxLife has constantly changed over the years, especially lowering the viscosity to meet the physical characteristic of lower initial viscosity ATFs like Dexron VI and Toyota WS, but there has been issues raised if it is truly backwards compatible with older DexronMercon specs.
Good example is Mercon SP vs Mercon LV issue - both are indicated to be compatible with new MaxLife DEX/MERC LV spec, but owners know that substituting SP in place of LV or vice-a-versa, will destroy that transaxle. Not a problem unique with MaxLife as this is a common issue with any universal replacement fluid.
Myself, as indicated, it is a mixed bag with my group of cars - only time will tell if MaxLife was a good choice for my cars.