Subscription Based Model vs One Time Fee. Thoughts?

Hey PH, So I work for SigmaOS (ihatemybrowser.com) and we are a productivity browser company focused on making working on the web easier. The current model is to charge a montly fee for the software but I have received some feedback from people that they would much rather pay a higher one time fee. I know there has recently been a little bit of a pushback against subscription based services but yet most services we use today are still subscriptions. What are your thoughts on this?