The worst upgrade experience may be my Logitech Harmony remote control - every time I want to edit it, a 40MB download is forced down my throat at a speed against which Nokia still was turbocharged on the first day of the OS2008 release, followed by a installation process that eats up all CPU for minutes.

And so far none of these "updates" has ever fixed a bug or added a feature - on the contrary, since I bought that thing, two features which I frequently used did get removed or got handling "improvements" that made them entirely useless, and the software is constantly getting slower, more bloated and less usable.