I have always heard great things about Aweber which is what I have and have used for the past couple of years.
Primarily I like it because the email messages usually get through and that is what I am interested in.
Lately I am hearing that I should use other brand autoresponders.
Which autoresponder do you use and why do you think it is best when setting up opt-ins on a clients website?
Thank you for your thoughts and experience with this.