Hello there, I've superb 280ps 4×4, just want a decent upgrade of the brake. It is stock 18R. Is it worthy to upgrade? Given that I'm driving only in town and highways, with few sprinting. Can I just increase the size of rotors and use high end pads?? Or to use BBK (expensive). Does anyone have experiencewith this matter? Thank you in advance

There’s a good few ideas to upgrade either keeping the same size as original and moving to drilled/grooved discs, or moving to larger discs - but you’ll need different caliper carriers and potentially calipers (not sure on that) so can get expensive. 
 

There isn’t a simple swap like there used to be Octavia vRS mk1 to Fabia Mk1 vRS.

 

All disc size setups are either FWD or AWD. Yours as AWD will be 340mm front and 310mm rear. Both swts of discs will be vented. Ignore anything that says 312mm front and 300mm rear as that’s for the FWD setups. It’s amazing how many places get it wrong.

 

 

One of the most cost effective brake upgrade is the 4 pot calipers from a Porsche Macan which will allow you to run a 340/345mm disc so would fit under 18" wheels. A maximum of 360mm discs can fit under 18" wheels however it will depend on the caliper setup.

 

Otherwise if you are not planning to go for more power then upgrade your pads and brake fluid which will help.

Considering your driving style and use, why upgrade? If not only for looks, I am not sure it is worth it. Maybe replace rotors and pads with a more "sports look" like the Brembo x-line series? Discs with holes in them. At least they look more, hmmm, aggressive?? And maybe paint the calipers.

Running EBC yellow stuff pads and BSD discs all round with braided HEL hoses. Better feel and remains solid while braking.