...having found your service by chance, we've been completely happy and pretty surprised actually. You offer a lot of features, with a very reasonable & logical rate system. ...How much your service will help is possibly beyond your understanding, but I'm sure you've heard that from other people using your service.
I switched to [Ezine Director] from Constant Contact not long ago, and I'm happy with your service. It's easy to learn and easy to use.
Great service! I have referred your service to a number of people.