If some company controls the network of proxies, you are not anon. Even if you pay with bitcoins, you will connect with an IP address that could identify you. You could use Tor to connect to these "elite proxies", but then why not just use Tor? If you need a non-exit IP, point the TorBrowser at a web proxy. Here's the site I use to find web proxies: http://www.publicproxyservers.com/proxy/list_country1.html