Use of Commercial vs Free Data Mining Tools

Poll

What type tools (commerical vs free/research) do you use for data mining and analysis: [192 votes total] Only commercial tools (45) 23% Mostly commercial tools (44) 23% Equally use commercial and free tools (24) 13% Mostly free tools (42) 22% Only free tools (37) 19%

Comments

tclimb, tools
What can you not do with a db engine, Perl, R, WEKA, and a host of free FORTRAN/C code (e.g., C4.5, CRUISE, etc.)?

Ali, Weka
WEKA is super

christian, OpenSource
With the R-Project and Weka i get all what i need. Reason's are Flexibility and continous development.

Karl, Tools and mobility
I'm in a sector where the work is all fixed-term contracts (UK university researcher), so every few years (sometimes less) one is forced to move on. Having previously been mostly a SAS man, I'm now at a university that has SPSS instead. So not wanting to be faced with the same situation in the future, I'm ignoring SPSS and learning R. That way I'll still be able to re-use scipts wherever I go.

Gus, Prediction Accuracy
From my experience I can tell that the free software available has THE SAME prediction accuracy as commercial packages ( SAS, Clementine, etc )
However, commercial packages handle more thoroughly the complete KDD process, model comparisons, etc