u can pay by credit or debit card for 1, 3, 6 or 12 months also you can buy a 60 day game card from most high st retailers. i.e Game, Gamestation, curry's, Pc world.
But paypal has that option to easily reverse your payment...
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@mut
I dunno about WoW, but in EQ the game cards were always a bit more expensive than paying by credit card, especially if u payed for more than 1 month at once. And I don't see why WoW would be any different so I bet the credit card option is the better deal with WoW also.