When an iPhone is released the spec's on it are right up there with all the others. But the biggest plus they have going for them is programming iOS to work next to perfect with the hardware they choose. So in essence, iPhone doesn't even need to have the best spec's. They know how to take full advantage of what they have and it in end makes everything work better than the latest and "greatest" spec'd phones.
On the iPhone i jailbroke, it was smooth as butter stock. I didn't do anything after jailbreaking, just jailbroke and gave it to him. As an IT pro i get this stuff, rooting a stock phone isn't going to make anything different. Same as jailbreaking. Its all what you can do with it after being rooted and jailbroke. As for the free apps after jailbreaking, it's pretty rare to see one of those paid apps we get for free crash. ik people with jailbroke ipod touchs, ipads, iphone's and they don't experience crashing problems. From what i've could tell it is the same exact app from app store placed on a file server.
Don't mean to start a war, but its obvious why iOS is doing so well.