Till now I thougth Feedburner was best but with an analysis I found I should have shifted to Aweber long ago
Here is a comparision of Feedburner vs Aweber
In FB you cant send email when needed while in AB you can
In FB the new subscriber will get the messages and emails from the current time. You can’t put any emails in order like welcome message, fisrt message after welcome, etc, but in AB you can schedule messages. Like you can fix messages to come at specific time interval after the user subscriber.
FB is free buy AB pays back tons of time more than what it take.
Recommend you to go ahead with near free trial of Aweber