I don't understand why some people still have wifi problems I have many customers ( now 85) with iPads all on wifi and absolutely no issues at all. I should point out again that many older modems do not like any of the new technology and in addition the settings for security if incorrect can cause issues with connecting to the net. I suggest if you still experiencing problems change your modem router / router. I recommend net gear
I have a net gear router, an I still experience issues with slow net speed using 4.2, I downgraded to 3.2.2 an the net speed is now super fast, shame as I love all the multi tasking on 4.2.