I am going to have to do some hairy scary statistics soon with large datasets.

Does anyone have a special package they like more than others.

My options appear to be SAS with a few added mods which our biostats department uses so I could have a bit of programming help.

Or R which is an open source stats package that is gaining quite a bit of popularity because evidently it graphs better. This support would be through the (R) community.

Does anyone here use either? Has anyone used both and has a preference?