Are Keyword Spy Tools Any Good

I'm been wondering for a while if any of these keyword spy tool are any good and whether they produce accurate results. Perhaps one way to check is to "spy" on your own website. I can see them working better for paid search rather than organic search.

clipped from www.ma1.se Discover your Competitions Profitable Keywords with Keyword Spy Keyword Spy will then tell you what keywords your competition are bidding on (you enter the URL of your competitor). Obviously its not going to be 100% accurate but will give you a prett ygood idea of what keywords they have optimised for!