I have done customer satisfaction surveys for the company I work for, last year "my best for return reply" I sent out 1250 surveys and received 324 response those who used the info was ecstatic and congradulated me on a great response so if you got over 600 then that is very very good. besides my survey was sent to those who we told it was coming and gave a prize for responding and still got a low return "IMHO" so congrats, even though it is not "scientific" you can still guage the poser community with this type of info

You might as well PAY attention, because you can't afford FREE speech