They will take the labels off unless you get the YTS retard doing it, so dont worry about that.
Spinning out at islands with 3 different tyre patterns on your car.. no wonder really

You'll notice an immediate improvement, not just because you have matching tyres but the lack of sidewall on the tyres over the 17" rims will keep you on the straight and narrow.
I know the guys at my local ATS tyres pretty well, i always wheelspin away and handbrake turn off their carpark to scrub the tyres off everytime i get a new set. (only when its safe obviously

)