How to differentiate Bux site and Aurora Site?

Tweet

As far as I know there are 2 types of PTC sites. The Bux sites (e.g Neobux, Bux.gs, Prosperbux, etc..) and the other one is Aurora (e.g Clix.vc, Dreamclix, etc..) For most part I do understand the differences but there are just some details about them that confuses me. So in your knowledge how do you really differentiate these 2 types of PTC? what are the specifications? is it the script? click rates? How bout Performancebux? it is using an Aurora script but is it considered as an aurora or a bux site?