Progressives are "progressive" wound and Race-Tech are not. I have had both on two different Maxes and like the Race-Tech slightly better. The Progressive dive more initially but stiffer up quickly. The Race-Tech dive less but have a stiffer ride. If you get Race-Tech get the .95 rated springs unless you weigh at least 220 or so. I have the 1.0 rated springs and they are too stiff as I weigh 160 dry. In fact, if anyone wants to swap Race-Tech .95's for the 1.0's, let me know.
I had put Progressive springs on my bikes since the late 70's till my last two bikes and was happy with the results. My last two have had Race-Techs. In addition to my Max, my 1200 Bandit had .95's and they worked great. Wish I had stayed with the .95's instead of going up to the 1.0's though.