I just read on iheartcvs.com that you can sign up here to become an advisor. A few times a year they will email you a survey and then credit your account for 2-15 ECB!!! I'm always up for free ECB!!
There was a couple comments made that just said that some get them with in a month or so and some still haven't got any surveys. So I guess it just depends but I think it's worth a shot!!