The problem is how similiar the users from these tool are like the ones of your product. Getting users from SEM hacks[1] might give better results. Don't know.

The problem is how similiar the users from these tool are like the ones of your product. Getting users from SEM hacks[1] might give better results. Don't know. Would actually love to see a comparison. [1] http://www.startuplessonslearned.com/2008/09/sem-on-five-dollars-day.html http://www.startuplessonslearned.com/2008/09/sem-on-five-dol...