I LOVE WYSIJA PLUGIN!
Yes, it's true and trust me, Wysija is very simple to use.
I used WYSIJA since I'm familiar with WordPress.org 4-5 years ago. I try Subscribe2 a couple of years back, but I get stuck with WYSIJA again.
And around 2 months ago, I tried other plugin which is Mail Chimp.
It's okey, but you can't design it in your own WordPress.rg Is like having a house, but you park your car with you neighbour. I just fell like having no control of what you want with the newsletter ...
Anyway, here I'm back again with WYSIJA, and also thanking WYSIJA for their excellent, simple, reliable, fully owned newsletter plugin by myself ... well at least that is how I feel it :)
Keep it up!