I understand. You could purchase it and ask for a refund if you're not happy. I won't get mad about refund requests, that's a promise.

Building a trial version was not a first priority before launching. It certainly is something I'll look into next.

On your website, explicitly declare a N days refund guarantee. It's a selling point, shows good service and people generally don't abuse it. Worst case, you'll remove it.

See number 7 in http://www.joelonsoftware.com/articles/customerservice.html

It's already there...

A direct quote: "You can try Radio Silence risk-free for 30 days. If you're not absolutely happy, you'll get your money back, no questions asked."

Sorry about that, missed it when I looked.

No worries.

If it came down to a choice between 'demo for 30 days then buy' vs 'buy, and 30-day refund NQA', I'd always go for the demo.

I'm not sure there's an entirely rational reason for it, but I don't think I'm alone there.

Incidentally, what happens if I ask for a refund, then use it block itself so it can't phone home for the revocation? :)

It's actually logical - if after the demo you decide that you don't want the product you just don't buy.

If after buying the product you want a refund you still need to contact the seller (or go through some automated process). It's an extra step.

As a seller though, I would think less people would ask for a refund than the group of people that would have bought the product, but instead downloaded the demo and then decided not buy.

Agreed. I use Little Snitch currently. I wanted to give this a try but.... I won't buy an application up front. I understand the Dev will refund instantly as stated in comments but it doesn't persuade me. I would even prefer a 15 day trial with a no commitment download. The only way to turn me off faster is to only distribute via the App store.