IPhone 3G upgrade to iOS 4.x - Don't do it if you haven't done!!

Every time I connected my iphone to iTunes comes up with a message telling something like there is a new firmware version until finally I upgraded from my old iOS 3.x to iOS4.x and now my phone is terribly slow :S


So if you haven't upgraded yet my recommendation is don't do it... Now a lot of applications crash, the phone is very slow even for apps like the calculator... I think Apple should pay more attention to provide better support for old iphones at least for some time, in my case I have 1 year with my phone and I'd expect better performance from firmware upgrades. The bad news is that I don't know if this happened to you but when I had iOS 3.x some apps that I recently update didn't work with iOS 3.x (like Yahoo music).

Let me know what you think of this and if you know an easy way to go back to iOS 3.x or better yet to ask Apple for better support on next releases of iOS.