I put on my 2012 Stryker. The ride is a little softer, which is what I was looking for. You adjust the ride by changing the length of the spacer at the top of the spring. Progressive called for a spacer length of 6". I ended with a length of 5 3/4" which makes the ride softer. If you want a stiffer ride make the spacer longer. If you are looking for a softer ride you could also experiment with changing the length of the existing spacer on the existing springs.
I was trying to soften the ride with the tire pressure set at the recommended pressures. The dealers keep wanting to lower the tire pressure to obtain a softer ride. But this results in more tire wear, more tire friction that hurts gas mileage and a mushy feel when cornering.
I also put on the Progressive rear mono shock. I am now satisfied with the ride. But changing the rear shot setting is a real pain.