I'm not going to get into the whole toyota owning aisin argument here, but I will tell you a little bit about my experience. I have a small auto repair business that I run out of my garage and I order a lot of my stuff off rockauto to save my customers money. I've used different aisin ATF products spec'd for hyundais, hondas, toyotas and they've all been fine. Transmissions all shifted smoothly like they should and I have yet to have one come and complain about anything. I used the valvoline full synthetic multi-vehicle atf(the red bottle) in a Lexus GX470 that was spec'd for WS and it was fine too. In this case the guy provided his own parts, but him having done his first service at 160k the transmission he later called me and told me how much better the transmission is shifting. Both in terms of smoothness and speed. I was welding up his exhaust a few weeks ago and he's now at 220k and the thing is going strong. I can probably give you a dozen other examples but they are all going to say the same thing. Get which ever is cheaper, they are both spec'd for the same fluid. You're transmission will be happier to be serviced on a regular basis versus what brand you're using. Change the filter every 100k.
