I don't think I agree with this one. I use OO's Calc on occasion (when I can't be bothered to wander from the lab back to my desk) and it really is just a shadow of what Excel can do. The scripting in Calc seems archaic compared to what comes with Excel. The integration between other apps in the Office family feels lightyears beyond OO.
It seems to have fitted your needs better than mine then -- the last time I wanted Excel to do something which KOffice KSpread couldn't do, Excel couldn't do it either. (It was a while ago and I can't remember the exact details, but it was something to do with taking a column of dates and producing a histogram of activity per month. I found a feature in Excel
called "Histogram", but there was something irremediably wrong with its bar widths or its axis labelling or something, and that's before I started attempting histograms with non-equal bar widths. Or maybe it didn't like histogramming date fields, or something.)
Peter