Since the models are static content anyway, perhaps try a CDN. Since you're already using GitHub, perhaps https://rawgit.com/ https://rawgit.com/ would be usefu

Since the models are static content anyway, perhaps try a CDN. Since you're already using GitHub, perhaps https://rawgit.com/ https://rawgit.com/ would be useful (mostly because it's free) until you decide you want something with guaranteed uptime.