I finally had a chance to try out some high rev up-shift today. no more blocking problem going form 1 to 2 and 2 to 3. The notchy feel is still there if I shift too fast but I can live with it.

My observation:

HKS: really sucks!
MT-90: better than Hks but only last 1-2 month.
MOTUL 75W90 GL4,GL5: the best so far, wondering how long it will last...

 

put some bg syncroshift in. Or shell helix if you have better access to thar.

 

can't get BG syncroshift in Hong Kong.
we have Shell gear oil but it is just the cheap one, what is the full name of it?

 

Shell Helix, it's the gear oil used in the Ferrari Enzo, ridiculously expensive, but apparently good stuff. More than $35 a quart IIRC, maybe more.