The obvious insurance considerations aside is there any reason I couldn't replace the standard fit 15" alloys (205/60/15 tyres) on my 2008 Octavia 1.8 TSi Ambiente hatchback with something larger - say 17" Octy2 VRs alloys (225/45/17 tyres) ??

Also would my existing wheelbolts fit?

If they are the same PCD (eg 5x100 or 5x112)

Yes they will fit and you will have no worrys.

Wheels bolts will fit.

You should be OK and wheelbolts ought to be fine.

How about something like these? VW,SKODA,AUDI 5x17" alloy wheels with225/45 tyres 5x112 on eBay, also, Wheels with Tyres, Car Wheels, Tyres Trims, Cars, Parts Vehicles (end time 25-Jan-09 20:24:13 GMT)

or these http://briskoda.net/items-sale/octy-2-vrs-new-17-wheels-tyres/134704/

Good luck.

Why not go for these instead

Skoda Octavia VRS 18" Zenith Alloy Wheels x 4 on eBay, also, Wheel Rims, Car Wheels, Tyres Trims, Cars, Parts Vehicles (end time 27-Jan-09 10:45:10 GMT)

If you change from 15" to 17" you will find the ride considerably harder assuming that you use the correct tyre profile to keep the overall wheel diameter the same. It's just a matter of taste but a number of people, myself included, have gone from 17" to 16" to improve the ride,

If you change from 15" to 17" you will find the ride considerably harder assuming that you use the correct tyre profile to keep the overall wheel diameter the same. It's just a matter of taste but a number of people, myself included, have gone from 17" to 16" to improve the ride,

.... but it is all a matter of what you are used to, prefer and will tolerate.

I run my vRS on 1s and find the ride perfectly acceptable; I have a set of 18s and think it is a smidgeon too firm BUT the shock absorbers are a more influential factor.

I say this on the basis that my vRS on 17s is fitted with Koni FSDs, whereas my wife's Roomster Scout has OE suspension on 16s; my vRS has a much smoother ride!