In my opinion, this plugin is useless unless you $pay$ for the premium version, as you can only send text emails to subscribers-- fine if you want to look like you are still living in the 1980's. The option to add html to format emails -- not that mind boggling an option really -- will cost $39 upfront plus a monthly fee - indefinitely- not much value.
I have no prob whatsoever that people want to earn something off their plugins. But I resent the fact that the free version has no formatting is buried deep within the product description. I feel that this this sullies the WordPress brand. I think there should be a standard that if a plugin is really more just a demo it should be made more clear upfront. Yes it's a free download but my time is valuable - a good deal of which was spent on installing and testing this plugin which now is in the trash heap/