As far as I'm aware the update from poser 11 to 11.1 is free. Just start up SM download manager and enter your p11 serial number and the update files should be available. Main advantages of p11.1 pro over p11 are fitting room, helps you fit clothes from any figure to any other figure, gpu rendering in superfly if you have suitable nVidea card, and rendering in queue or background. As very much an amateur these (and the copy morphs from feature) are the only "pro" features I use.