it all went well, managed to scrounge 4 std valves and a strip of balance weights from the local tyre depot.

Thanks to drakes for his advice regarding balancing. fitting the valves was pretty straightforward and I assumed that the rubber valves would be 5g lighter than the TPMS ones and so added a 5g weight next to the valve. wheels feel perfectly balanced.

the car drives better now with a significant improvement over worn road surfaces and also a couple of minor but irritating rattles have gone, I suppose because of the softer ride on the higher profile tyres.

the wheels fill the arches better too. I'd say they stick out by about 20-30mm more and gives the car a better stance as the std wheels look too far inset to me.

all round, a major improvement