my NB heatsink was never really hot to the touch (445 FSB, 1.35 vFSB, 1.425 vMCH for daily use). it would get warm at the base before i put the fan on it, but never so hot i couldn't keep a finger on it. but i do have an Antec 900 case with a 120mm side fan, so airflow has always been really good in there.

Miwo has an Enzotech heatsink, which explains why it would feel hotter to the touch than my stock one. Enzo makes good stuff and a hot heatsink means it's transferring a lot of heat, which means it's doing its job well.