iOS 4.3.5 has been terrible for me. I've tried restoring the phone back to factory, and even gone as far as re-downloading the iOS 4.3.5 update, but nothing has seemed to fix many of the problems I've had with it. I experience probably 4 to 5 hard freezes per week, where I have to hold the power and home button for the 5+ seconds or whatever. WiFi hardly ever reconnects properly. I usually have to manually click to connect to my network and school network. Bluetooth sometimes doesn't connect to my car. Whenever I 'restart' the phone, in hopes to fix some issues, my apps rearrange themselves to some other state. I can put an app inside a folder, turn off, then turn my phone back on, and the app is then back on the 2nd page of the home screen. The Phone Application sometimes freezes. Pressing End doesn't work. It just gets stuck on a call. I have to do the home button + power button, or else, the phone will kind of do a fake reset, where it starts to shut down, but then comes right back to the home screen. Often, when turning the phone off, it will go back to the lock screen. I can actually unlock the phone and use it, but then it will finally shut off. Needless to say... iOS 4.3.5 sucks for me. I hate it. It's almost as bad as Windows Mobile IMHO.