I never have extended warranty on smal stuff (under £1000) such as TV's, I put £100 a month into a savings account and recently robbed it to help buy GS as it was buuilding up.
A £500 tv is one thing, I can afford to replace it, over the years this has served me well, these things normally last 4-5 years so extended warranties normally run out just before the blow up, and of course this years £500 TV is next years £300 TV.
I cannot afford £1200+ for an FD, or for a new engine if it blew, in the past I have taken the risk on other bikes, with all the doom and gloom regarding FD / EWS / FPC / ABS Controllers on the GS I will pay my £300, there are just too many doubts for me personally.
As stated if nothing goes wrong I have wasted my money, but if I spend £300 and never have a problem for the year I will be happy enough, I consider it part of the cost of GS ownership, just like insurance, tax and servicing and adding it all up at the moment it seems worth it.