Well, Its personal opinion......

Don't worry about the rear brakes, their only there to stop the back catching the front. Although a slight increase in disc diameter, its the same calliper and pad on the ST170 & RS.

The front is a problem. You can get 'better' discs and pads which can increase the braking effort and feel. As with tyres and many other such 'comsumables' you'll find a large range of opinions on what is good and what is bad.

Unfortunately, the strange design of the front knuckle means there is no easy modification to a bigger brake. The easiest is to fit the ST170 knuckle/hub, discs and callipers. The knuckles alone are a good start for other more serious upgrades through to large, but expensive, AP kits.

You can get a kit of new Ford ST170 parts, but pre-used are still around from recycle yards.

Martin