Just a heads-up for anybody thinking about going to these shocks.
On the good side, they improved the ride dramatically over the OEM shocks. The Progressive's are great shocks. Getting rid or the OEM shocks was the first thing I did with the bike, and it made all the difference in the world on both short and long rides.
On the down side, the seal on the left side shock blew out in about 3 months (sprayed fluid all over my rear wheel and rear of the bike). I took them back to Progressive (conveniently they just moved down the street from me to Buena Park, CA) and they rebuilt the shock at no cost (I think the shocks have a lifetime warranty on the internals). Progressive rebuilt it in one day (very nice!).
The guy at Progressive told me what caused the problem. With heavier bikes, if they are parked for too long on one side (kick-stand), the seal can blow out. There was a little more to it than that, but thats the basic story. I had parked the bike for about 3 weeks when it happened. The solution is simple. You have to park the bike on a center stand or in a wheel chock so it is parked straight up. Eliminates the problem. Keep that in mind if you get the shocks because although Progressive will rebuild them, taking them on and off is a pain.