I use it for the Excel equivalent. For some reason, even though I was always installing all the "office" programs together, the last time I tried to install everything, it told me I had already installed Excel too many times, but let me install everything else. GO figure. So now I use Open Office for anything excel based. The only "problem" with the Excel equivalent is that there are a few differences in how you enter formulas. Nothing huge, but enough to be slightly annoying at times.
But yeah, over all, it works really well.