The main benefit to using a miter-saw stand involves the stability, and thus accuracy, of your cuts. Plus, it is far easier to cut long stock while using a stand. When choosing a miter-saw stand, you have a lot of options. Some fold up, some have wheels and others work with extensions, which are especially handy when cutting long stock. Get more great tool reviews at www.toolselect.com [2].
Links:
[1] http://www.youtube.com/watch?v=OlcxLX0M2R4
[2] http://www.toolselect.com