I think this is an excellent way to acquire paying customers AND will give many potential users the option to see if they can build a decent subscribership without having to front the $250 or more that would be needed for ListBuilder.
I just started my first email campaign for our warehouse sale that we do twice a year. This is really great!! I even cut and pasted the signup form onto our website, saving one of our participants hours of time receiving emails and adding email addresses to our in-house list. Wow! I love you guys. Where do I send the flowers?
Ezine Director is one of the best and cost effective list managers in the market - I have used quite a few.