I think you need to be more clear regarding your payment structure because it's ambiguous on your site. You state 'one time payment' which suggests you 'own' the plugin once bought and just lose the ability for updates rather than the reality which is that you are just hiring the plugin for a year and after that lose the ability to use it without paying again. Photon IS just another subscription model the only difference is you don't auto charge. Tbh i don't like the model at all and think you should offer a permanent license option. It just puts me of using it i don't want to pay £550 for 5 years usage with no ownership in sight and have to keep paying in order to access work i've done with the plugin. It's VERY expensive at the moment considering there is never the possibility for ownership / permanent license.