Works great but…

Nice and simple interface, easy flow.

But something to consider: Cost $100 to remove their links from every email you send.

You cannot schedule campaigns and create autoresponders in the free version. The admin area shows:

For 100$ one-time fee you will get additional features:
Remove Mail Masta footer from emails
Schedule campaigns
Create autoresponders
1 h priority support

Nothing wrong with making money, we all have to, just wish I had known all this before installing.