Did you find that the iPhone 4 was better than the 4S?
I found that there was no difference in the vast majority of day to day use between the two. Yes, the camera was slightly better, but Siri is a vitually worthless gimmick and the processor upgrade was undetectable to my eyes.
I felt that having the difference in money between the two models was preferable to having a very slight camera upgrade on my iphone.