I'm guessing the colored models will be very popular. They will be good enough and be cheap (for an iPhone)
Why will anyone buy the flagship iPhone?
Presumably Apple will deliberately cripple this phone in some way to keep is worth than the more expensive model in all aspects by a noticeable margin.
A cheaper model needs to be "Worse Enough" so that there will still be enough people who want to pay the extra for the better model.
The problem comes when you make the cheaper model too good and damage your high end sales.
Problem for Apple is getting the balance right between worse enough, and not seeming too worse when put up against competitors phones selling for the same money
Apple being Apple won't price this cheap as they will still want to made sad people feel as if they are better than others as they own an Apple product