Constant Contact, Mail Chimp, BombBomb??

[Scott Speer]

OK BP Peeps need some help and input?  I am looking to send out emails on deals (Wholesale, Retail, Investment Properties for sale) from time to time and am trying to decide between Constant Contact, Mail Chimp, BombBomb or any other type of email service, what have you experienced, what do you like and don't like and why, what do you use your for?  I have a list of emails from investors I have collected over the years and use my Yahoo email with BCC, but would rather use a service that will allow people to Opt out if they would like.

Thanks for taking the time to give me your input!

Sincerely,

Scott S