Has anyone used the Return Path service. Specifically is it worth going through their certification program to improve deliverability.

We already do much of what their looking for. In their program you pay them an annual fee based on your email volume.

Once you pass, they supposedly put you on a whitelist that gives you better deliverability into isps.  

I am not sure they are actually doing something other than helping you help yourself, by doing best practices.

Anyone had any experience with them?

Regards,

Will