With all the negative hype surrounding this product, I was skeptical about it when I received it. And man, I was not let down by Apple.
Speed:
This is one of the fastest phone I have ever used. My previous phone - HTC One X was plenty fast but, occasionally it would stutter and slow down until an app would crash. With iPhone 5; it was very hard to crash any apps. For example: on an iphone 4, if the app is already opened once it reopens fast until you've cleared it from the app tray. On iPhone 5, it doesn't matter where it is opening for the first time or has been cached. This is most visible in 'Settings' app.
Screen:
The screen is gorgeous. It easily surpasses HOX, SGS3, GS Captivate, iPad 2 and iPhone 4. And, it is bright enough for use in direct sunlight.