Clubsport S - 18 Inch Wheel Advice

[MinchCS]

 
They are the same diameter / rolling circumference as the Prets I took off - actually a mm or two less - but the 225s looked too small, and the extra sidewall (marginal) is worth having.
One word of caution (if you haven't thought of this already). Make sure you keep 5 OE wheel bolts in the car for the space saver if you run one as the OZ ones are not the right fit. And keep the thin walled 17mm socket with them, because the VW wheelbrace is too fat.

[GTIreland]

There are two things that made me hold off from installing 235s, namely the insurance factor as they are non-standard size and the lack of resources to determine what the new ideal tyre pressure might be cause it's almost certainly not 36psi anymore, probably somewhere between 33 and 35.

I did consider the wheel bolts/socket situation in case of a puncture but my tyre fitter sure didn't as he installed the OZ wheel bolts to my new Belvederes! Only noticed when I got home where I promptly swapped them around however the only difference that I could see was the length of the bolt.

[MinchCS]

I notified my insurance company (NFU) re aftermarket wheels and tyre size but no adjustment to policy / premium required.
The OZ bolts have a subtly different seat profile.
As for tyre pressures: the 235s are 95Y and I am currently running at 37 (Clubsport S door plaque says 39 for 19s).
But you can overthink all this....