Value for Money
Try the free version before going to the payment plans, they have almost all the functions of the premium versions and can serve the majority of small companies.
The massive sending of emails is very simple, with prefabricated templates and the ability to save the templates that one creates. Simply copy and paste the content and the program takes care of the rest, has many options for managing subscribers and is super easy to learn to use.
None so far. Sometimes it can be difficult to find what I'm looking for when I'm navigating their site.