You received a '1' from me because you didn't give me the ability to say 'no thanks' or 'ask me later.'
You really need to start listening to your users. Especially those of us who paid to use it. Or you'll soon be looking for another email app to purchase and ruin. I'd guess that the only honest ratings you're getting are from people using the free version.
Speaking strictly for myself, the fact that I paid for the app should show you what I think about it. To force me to give you a rating is simply not right. I never respond to surveys, I never rate products or apps, and I don't write reviews. If I like something, I will pay for it. Otherwise leave me alone.