I had to replace my clutch master cylinder this weekend, because my old one was leaking into the car. I had purchased one of Rodney's a few days before, and it arrived in plenty of time for me to do the job Saturday.
Rodney's master cylinder is made of cast aluminum, not iron like the kind you get from the parts store. The fluid container is also attached in a better way than the parts store kind. On many of the parts store kind, if the cap gets stuck, you have to be careful not to twist off the container when you try to remove the cap. Not so with Rodney's.
Rodney's comes with a bench bleed kit, which makes preparing the cylinder for installation very easy. I had mine on the car in no time at all. It also comes with his adjustable banjo, which I adjusted so that the clutch pedal was about 1/4" above the brake pedal, as I have heard that it is supposed to be that way.
As for how it works -- very nice. I used to have to press the pedal all the way to the floor to change gears. Now the clutch disengages with the pedal about 1/2 the way down.
If your clutch is giving you problems, and you see your master leaking, I recommend you get one of Rodney's. You won't be disappointed.