For faster road riding and track riding I would suggest linear springs are definitely the way to go though again make sure you get the right ones for your weight.
Edit:
See http://www.promecha.com.au/springs_advanced.htm
"Progressive springing is much less popular for road-racing, with linear main springs used almost universally. There is a good reason for this: going around corners compresses your suspension, by quite a lot with modern race tyres. With progressive or dual rate springs, that means the suspension is going to be stiffer than when upright. However mid corner is also where you most need good grip and would really prefer your tyres not to be bouncing off the ground."
"Dual or progressive rate springs are really a compromise that allows low-speed comfort without excess bottoming, which is why Honda fit them to road bikes. Racing is not about compromise, so they don’t get used for that."
Edit:
See http://www.promecha.com.au/springs_advanced.htm
"Progressive springing is much less popular for road-racing, with linear main springs used almost universally. There is a good reason for this: going around corners compresses your suspension, by quite a lot with modern race tyres. With progressive or dual rate springs, that means the suspension is going to be stiffer than when upright. However mid corner is also where you most need good grip and would really prefer your tyres not to be bouncing off the ground."
"Dual or progressive rate springs are really a compromise that allows low-speed comfort without excess bottoming, which is why Honda fit them to road bikes. Racing is not about compromise, so they don’t get used for that."