We have had heaps of PMRs which go to IBM Korea and unfortunately everytime we get same one or two guys working on it and they are absolutely rubbish.
If I remember Jin Hwan Hyun is total waste of time, we end up finding solution ourself and closing cases. How is your experience with overall support?
My experience is that the paid IBM support for DB2 is very good (at least in Netherlands/Belgium/Germany or UK/IE etc), PROVIDED that you understand how support works, and the difference between defect-support and general support. The best results come from being able to do basic problem determination yourself, in addition to providing whatever evidence the support teams required.
There's always another side to the story, so I would never single out individuals in a public forum.