i've been using ios7 since the first beta & each one has been a considerable improvement over the previous one (beta 3 I used for a few hours then went back to 6.1.3, the phone was un-useable!) From beta4 onwards, the phone was useable on a day to day basis albeit with a glitch here and there but nothing serious.
Been on GM since day one, hand on heart, the phone is PERFECT! i cannot fault it anywhere, or write here one single operational complaint simply because I don't have any! the phone is faster than ios6, battery is better, no lag, no crashed apps, NOTHING, ZILCH!
Yes I agree that having an iPhone 4 means that I lose out on some of the new ios7 features but to be honest, it doesn't bother me at all.
I was thinking about getting a 5S but now after GM i'm not so sure especially bearing in mind that my 4 is in brand new condition!
What I am happy / thankful / grateful for is that once again Apple has supported & updated its "older" devices with a brand new operating system on an annual basis and FREE OF CHARGE, other companies please take note!
You don't build a solid & long term customer base by "shutting" out customers!
WELL DONE APPLE!