If they're using the 5S internals, why not just buy a 5S now if you're waiting on this? They're both 4 inch phones but one uses quality materials like aluminum. So silly.
If the internals are going to be exactly the same as the 5S then I agree, there's no point to making this phone. I have to imagine there's going to be something more, perhaps the 6's internals, to make this viable.
Where I disagree with you is the comment: "They're both 4 inch phones but one uses quality materials like aluminum. So silly". When did aluminum become such a "premium" material? Sure it's light but there are definitive advantages to using a quality plastic or polycarbonate material.
For one, it absorbs shocks better than aluminum and, when dropped, less of the kinetic energy is transferred to the glass.
Secondly, it doesn't need antenna bands; the signal can pass through any part of the housing.
Thirdly, it won't scratch or show wear as badly (in most circumstances). Let's remember how poorly the 5 held up to basic wear and tear.
Lastly, most iPhone users I see have their device - their aluminum (premium) device , in a plastic case. The irony is befitting.
Aluminum is a fine material. It doesn't, however, fit my definition of premium.
Just my $0.02 - to each their own.