iPredator is using pptp which is very insecure. (The original authors of the protocol recommend that you shouldn't use it). It is also considered to be cryptographically broken as of last month. (http://en.wikipedia.org/wiki/Point-to-Point_Tunneling_Protoc...)

A list of reasonable VPN providers is available here: http://torrentfreak.com/which-vpn-providers-really-take-anon...

(If you are using a VPN, you have to be aware that there is a lot of snake oil. Finding a good VPN provider is very difficult, and then purchasing the VPN anonymously is even more difficult.)