My dealer tells me that the 530 and 550 are the same camera labeled differently because of some distributor legalese. After reading thru the manual it looks and programs the same with all of the same features.The camera's been in for 2 1/2 weeks now and I'll replace the card on the 25th. Last year at this time new bucks started showing up that I hadn't seen all summer so I'm hoping that happens again. So far I've got 2 nice shooters for sure that I'll be looking for on the 24th. Good luck fellas.