how good are the estimations from the g traffic estimator tool?

[NewKidOnTheBlock]

For German sites we dont have any real kw research tool (we got google adwords that shows a colored bar that sometimes gives me the opinion it could be just about anything..as it only seems to compare the chosen keywords to one another - so its hard to gauge how much traffic theres in a niche. Plus we got the overture tool which has to be trusted even less than in the US as yahoo's market share is < 5% here.)

Now I just used the google traffic estimator tool and google actually gives me numbers for my german keywords. An average of other people's PPC campaigns if I understood it correctly?

Would it make any sense to use these search volumes to estimate organic search traffic? I guess the numbers will still be nothing but a very rough estimation (as I have to guess the organic volumes from the clicks on the paid listings), but it seems to give me a better idea than the colored bar of the adwords tool (let alone inventory.de.overture.com). At least it seems to enable me to guess that the traffic for the organic listings are similar to those for the paid listings multiplied by a factor x (which could be anything) if these numbers are correct.

Can I trust these click volumes or can they be way off, too at times?

[AussieWebmaster]

They never give total searches and postulate a number based on a made up CTR.... position/bid/etc - there are just too many variables for this to be anywhere near accurate