Just interested in everyone's thoughts....

I am planning to buy a 5DII and have been doing some research on price. DWI have it for a great price $2,500 (ish). I just went to the local camera shop to find out how much i could get one for duty free - $3,100 (ish). The local store has small perks like free sensor cleaning & they hire lenses to people who buy camera bodies off them which could come in handy. There is also the Canon Australia warranty HOWEVER $600 is a BIG difference and I am definitely not made of money. It seems like a no brainer money-wise but I am concerned about warranty issues on the grey market cameras. $2,500 is a lot of money to lose if something goes wrong & the grey market warranty is dodgy. Anyone had any good/bad experiences with items being purcahsed or repaired under warranty by either DWI or DDP?