I recently installed one on my Venture 21 to replace the clumsy triangle sheet system. Boy! What a difference it makes both in mainsail control and speed. It's also safer when ya get hit with a big puff as easing is quick and effortless. I set mine up as a end sheeting system rather than mid boom for better control with the caveat that in certain situations, the mainsheet can interfere with the tiller. Modest planning addresses this easily and the pros far outweigh the cons. Now I can sheet out to the shrouds if I like rather than the 50 or so degrees of the stock system and it's FAST! I got slammed with a big puff that laid the boat over to 45* and made her want to round up and with a simple jerk of the line out of the cam cleat, I was able to ease within seconds, maintain boat speed and flatten her out. Once the puff passed, I simply trimmed back in with one hand. Total cost for all components (I replaced everything) was $ 416 and change. Now I can use those old pulleys as turning blocks for the new Assym I'm eyeballing, when I get some winches on the boat.