Downgrade iOS 6 to 5.1.1

I have an iPhone 4 and I'm resident in Japan. Until now, with iOS 5, the iPhone was my life-saver to go around the places: accuracy, possibility to input names (and get them found) in kana/kanji as well as in alphabet, public transport combinations, etc.

I updated to iOS 6 believing the Apple promises of "new and better features", and now my iPhone is a useless brick! IOS 6 Maps is only good for the US, maybe! We don't drive around everywhere in Japan, we ride trains and use public transport. IOS Maps external appls links just make the application collapse and I have to restart the device; doesn't find places... IT´S a HORRIBLE DISASTER.

Instead of the apology letter from Apple, could you allow the downgrade to iOS 5 even if it was for a few hours, so that all these people like me who are now extremely frustrated could roll back to have again a useful device?

I thought Apple's iPhone was a great device; but now, when there's a minimal request, I feel prisoner from Apple's ****** decision. I honestly don't see the customer friendly attitude here. Absolutely unhelpful on the phone; no solution.