This post is more than 2 years old.
So this probably falls into the 'No Duh' category. I needed a good iPhone simulator and had Googled around a bit. I found a few web based ones but I needed something that would work alone as an application. I found one application that worked ok, until I needed to scroll. For some reason, it had no support for scroll. What the heck was that about?
Anyway, in one of my searches I was directed to the iPhone SDK (http://developer.apple.com/iphone/program/). I had initially ignored this as I had assumed it was only for writing iPhone applications. While that may be it's main intention, it also comes with a darn good iPhone simulator as well. You should also ignore the prices for the iPhone Developer program. This SDK is free. It is a huge download and a slow install for one small tool, but it's definitely a good simulator.