My Dad has the same engine, and we just did his transmission. We went back to Z1 because it has worked quite well for him.

For a Honda, I'd say Honda fluid. Others have had great luck with synthetic, Hondas I've had have just seemed to like the OEM stuff.

Molakule once said in his post that Z1 is different by having ZDDP that other more modern/universal fluids do not use anymore. The ZDDP plugs up the porous clutch pack materials but seems to help Honda's Manual like automatic transmission.

He also mentioned that there are other additives that can replace ZDDP in a tranny and that's what most fluids use nowadays.