I haven't owned any of the top-end Samsung phones either, or Android false stop, but I've got to a point with Apple where I'm willing to give anything else a go.
My main iOS/iPhone gripes are:
1) You can't set notifications per email account. Its one setting for all.
2) Home button losing its sensitivity and needing re-calibrating. Constantly. On all handsets that I've come across, and I've come across loads.
3) Being stuck with the amount of storage the phone comes with. Non expandable.
4) iTunes and syncing of media... i.e. lack of drag and drop/mass storage ability.
5) No "true" multi-tasking.... i.e. get a message and you have to stop everything else (bar music) to deal with it.
6) Battery built into the handset so no option of carrying a spare battery if ever needed.
7) No flash player.
Most of what I don't like like about iOS/Apple is basic stuff that can usually be found on the most basic of devices.
Eye recognition; I've been using smartphones for 10 years + and never had it switch off on me whilst I've been reading / using it
To be fair, the screen doesn't usually switch off, but it does dim, almost all of the time. It only requires a tap of the screen to get full brightness again, but it still irritates me, especially in the middle of a game!
I'll be receiving my Galaxy S3 later this week and who knows, after our bonding/honeymoon period it might irritate me too. But I'm going to give Samsung/Android a try, because like America and giving oral sex, its something you should experience at least once in your life.