I'm a big fan of Motul.
I, too, fell down the Samba trans oil rabbit hole and subsequently gave away the gallon of Swepco I had left over from my 911. (I can't remember if it was 201 or 202, but several people suggested it was great for 901/915, not so much for VW axles)
As part of my regular spring ritual last year, I drained and filled my trans with Valvoline or Castrol synthetic gear lube. It shifted so poorly I thought my cable shifter had gone out of adjustment. I switched to whatever Motul is Dino (Gearbox300??) and it shifted like butter. And still is after however many miles I put on it last summer. I'm not even going to change it this year unless I experience shifting issues.
Ironically, my motor is exactly the opposite. I tried running fancy Motul 300V in it (because I can get it for free) and it sounded like a box of rocks. After another epic Samba thread, I decided to run straight 40 weight* Rotella T2 in it. ($8/gal) and it purrs like a kitten.
* Mostly because my oil light was flickering at idle when warm with multi visc. Slapped a pressure gauge on there and it's got 6-7 psi at idle, so my sender is probably a little wonky. But it doesn't do it with straight 40wt.
I also use straight 40 W Rotella to which I add STP oil treatment with zinc. Works for me and it’s inexpensive.