Just in case you didn't go to school that day...
The audible spectre a human ear can hear is 20-20.000hz, and that's why the iphone and ipad give you a 20hz to 20.000hz "frecuency response".
Sure you can go higher and lower and it will result in a little bit more clear and deep sound but not as really noticeable as if your ears could hear the complete spectrum. Also there are a lot of factors apart from bandwith that affect audio quality like impedance, SNR, distorsion etc... and of course
the audio file format.
My AKG K612PRO is capable of 12hz-39500hz and I don't know what kind of sorcery is that, but hey! it does it through a
silly cable that's unnecessary, prehistoric and constrains the user!
Audio quality is not relative to the damm freaking port, but it is for audio file format-compresion and the input-output set-up. So let's cut to the chase, we are talking about the iphone here. So what? Are you going to listen FLAC songs on a 16GB device? Good look with that, maybe you will be able to storage one full album.
If you want to give Apple another reason to milk your pockets, go for it and buy it!
and maybe buy it again every year when the port breaks.