My glass on my 4s scratched like crazy. Not sure what you mean by unscratchable. Wiping and then laying gently on my desk yeilded scratches the first day
Who knows how this will hold up but the drop tests pretty much prove it is sturdier than the last gen.
Yes
I will prefer scuffed aluminum over scratched glass and I also prefer both to plastic.
I have man'd-up and removed my blk iP5 from my slim plastic case and am loving it. Some nics on the chamfered edge but no scuffs yet. It might be a case where once it gets evenly scuffed it will be just right (example - my scuffed as **** titanium wedding band is awesome).