Kind of my point. You don't have to jailbreak an iPhone to get response.
How many dud iPhones have you ever heard of? I hardly believe the hardware is at fault. I'm going to bet that a ROM change will probably improve things. Still - why should it be necessary?
iPhone out of the box is also sluggish as hell. Slow animations make it feel sluggish. Install FakeClockup and it allows you to speed up the animation and the phone is a different animal.
Well I don't really understand then what the issue is, I have stock standard S3 and it is smooth as butter and faster than my iPhone.