Do you need a good P2P game or do you need a description of P2P vs. Cash shop?
If it is the first:
Dungeons and Dragons Online
Lord of the rings online
EVE
WoW
Age of conan
If it is the second. Because in F2P games with Cash shop u can buy overpowered things which will make you overpowered in PvP and PVE. This does not exist in P2P games, because you all pay the same price.