I see that there is a list of accepted http status codes that I can modify, but I think it would be cleaner if I can get the http status code in the failure block ..
In newer versions of AFNetworking, you can retrieve the response object from the error:
[[[error userInfo] objectForKey:AFNetworkingOperationFailingURLResponseErrorKey] statusCode]
This is handy if you're doing error handling further up the line and don't want to pass around the response object.