It's intuitive (I didn't look at the documentation) so I can show the kind of technophobes that blog on our website how to use it without them hyperventilating (I haven't lost anyone yet) and it does everything I want from it.
You can also buy an add on from Acymailing that allows you to add the blog to a newsletter. Brilliant.
Their tech support is the best I've ever come across. I emailed them with a problem, had a reply in five minutes and the problem was fixed within 30 minutes (possibly less, I only looked after that time).
I'm an old curmudgeon, so this is high praise.
It's easy to use, has good documentation and with the wonderful feature of tags you can set up a newsletter by just adding a tag.
I can't recommend it highly enough. This is the best program for the job paid or unpaid. Grateful thanks to the development team!