Just been looking at upgrade deals and came across this. At £9, it's a cracking deal in itself but has potential Quidco payback of £90 which would make this £18 for the year!
I have crap coverage on three in my office (they have only fitted vodafone boosters sadly) but I am VERY tempted to go for this still. Thought it may be of interest for others.
Remember - quidco is never guaranteed!
£30 quidco it comes under the 1gb cashback