The program is easy enough to use. Drag and drop your source folder or files onto Scriptm, the .JS and .CSS files are listed, and you could just click the Optimize button right away. The minified versions are saved within a few seconds as separate files (original.css > original.min.css), so you don't have to worry about the originals being overwritten.
Scriptm reports both the original and new files, and displays how much you've saved. This initially seemed very impressive on our test PC, with reports like "83% decrease", but it's a little misleading. The figure relates to the finished file size, not the saving, so "83% decrease" actually meant our file was 17% smaller. But once you understand that, it's not a problem, and there are useful savings to be had.
Scriptm isn't doing anything too surprising, but its interface works well and the Real Time mode is a plus.