I think £40 for a BluRay series with that many episodes is good value. If you shoved that price on DVD however (what I buy) I would say no.
I used to be tight arse dependant on my want for a series and just how blind buy-ish it is, and still kinda am dependant on my outgoings each particular month. A mortgage does that to you lol. Imagine waiting for Birthdays & Xmas for the bulk of the animes you want that you're not a price stinge with then welcome to my world haha.
So yeah I am happy/perfectly fine in saying that Kill La Kill to me is a proper rip off when you consider what part 1 of AoT is going for for more episodes and I'm jealous of all those with the money they have to part with for it and a lot of high cost kickstarters hehe