Flow direction of the cpu fan... question.

I have an Alpha PAL8045 heatsink with a 40cfm panaflo. I have always had the fan blowing air away from the heatsink. One of these days I am going to see what my temps are with the fan blowing into the heatsink, but I'm just curious what most people do? I know with the popular slk800 everyone has the fan blowing onto the heatsink, but I remember when I bought my Alpha there was a mix of opinions on this, at least for heatsinks like mine.

There was a thread on this just a few dys ago you can find it here-
http://forum.oc-forums.com/vb/showthread.php?s=&threadid=203738

I personally have it blowing into the heatsink. The one disadvantage of that is that more dust tends to get trapped in it.

Thank You,
Daniel