I got this for ten dollars at a garage sale - It is Fun Fun Fun.  I'm working my way slowly through the Protos missions - it is very challenging and probably too hard for anyone under 12 to get into.  The game uses literally 8 buttons, 12 if you get the hang of using quick keys to toggle map coordinates.  Eventually you could master everything to this game, but it will take weeks or months.  This is a good warm up for anyone who wants to learn Star Craft for the PC or to play casual with some friends - with the expansion pack it looks great on my 40 inch HDTV.  Best game for the N64 except Goldeneye 007.