Verify email quality

As many of our SaaS apps are based on using email as the signup mechanism, how many of us would be interested in validating if the email address used is of a reasonable good quality. By quality I mean the system will generate a score based on a bunch of parameters such as.

1. Not a disposable email address
2. Domain registration validation
3. A well known email address
4. An active domain

And a bunch of other validations. It will do these actions close to real time and respond with a score between 1 - 10 where 1 means don't trust the email and 10 would be absolutely trusted.

If this email validation is available as a service would you be interested in paying for such a service.