Well, guess it all depends also on the browser you're using. I was used to surf with Netfront 3.1 on my Sony Th55 which is 320x480 like the iPhone, and (tought to be) happy with that.

Now I know how it su##s to browse the Internet on such a low resolution, you always have to refit the pages or (if you're lucky to have something like Netfront that can show up pages in their full size)to scroll them right - left.

I wouldn't go back for any reason (tough the other uses of the Sony which I still have are great, like PIM and other PalmOS programs)