Re: "It'll also trash your add-ons"
I don't know what exactly transpired with illiad's encounter with forced upgrades but I have a story of my own about that.
I found myself saying WTF when I had thought I had it set not to and I still got hit by an upgrade. Then thought maybe I just forgot to set it. So I went and made sure it was set. I was even paranoid and rechecked to assure it was in fact set. Then got hit yet again by another one. You don't even want to know how pissed I was. I honesty think FF did issue some forced upgrades at least a couple times.