If you have no intentions to overclock what so ever, my recommendation would be to stay with the 4771.
They are the same CPU, at some stock speeds. 4771 could pull ahead in some applications due to having VT-d and TSX enabled.
But non of those will be utilized for the general application.
I dont see a reason to go with the 4770k if you dont want to overclock, there are absolut 0 reasons to.
Even if you will overclock, I would only advise it if you could change it for free or for a VERY low price.