Jetabroad.com.au (Australian travel agent) is offering 20% Cashback if using Paypal to book flights with minimum spend $A750 and maximum cashback $A400. The site will book "anywhere to anywhere" and I have been looking for a one-way LHR-SYD in October 2010, which I would generally book about 8 months ahead to get lowest (Y) fare (at about $A800). I can now book the same fare 12 months out at this price (after cashback) and still fly the QF A380. It's not much more to fly via LAX (with a stopover). Is there any problem with this Paypal cashback or is it a really good discount?