Well speaking for a 93 del sol si. I've tried 10w30 (dino), Honda MTF, RL MT90, RL MTL, and GM syncromesh Friction modified.
10w30 - did not work well at all, hard to get into first, gear grinded from 4 to 5th at rpms above 4500rpms.
Honda MTF - Pretty much the same except 1st gear was better...