Another way to keep the rigging from flogging while sailing and at anchor: I purchased a second boom vang which I use with the one already rigged. I read an article about a 36' C & C that used a double boom vang system to keep the boom from swinging wildly in heavy weather and acting as a preventer. My M15 does not have the space to duplicate the C & C's setup. My setup is a little more cumbersome but it works fine. In rough weather or anchored (3 nights at Catalina Island), I unhook the base of the single boom vang from the mast and attach it to the starboard side chain plate (stern hole). I have a shackle attached to the stern hole of the port and starboard chain plates. I also have snap hooks attached at both ends of both boom vangs for ease of connecting. When the boom vangs are cinched up (not real tight), they keep the rigging from flogging in puffy winds, rough water and at anchor. It takes a little to practice to tack with however. At anchor, I attach my spinnaker halyard to the end of the boom and tighten both port and starboard boom vangs to make a very solid setup. I can put my full weight on it without movement (it's secured in four locations). I also use flopper stoppers which work very well in reducing movement. Last week end in vary rare thunderstorm, I attached the second boom vang in order to keep the rigging from being flogged senseless. Once attached and adjusted, the rigging was firm and secure. I saw the larger boats heading into the harbor so I decided to do the same. I turned into the wind (irons) and lowered the jib. To my amazement, the boat took off at about 3.9 kts (GPS) almost directly into the wind! I had the tiller centered with strong bungee cords. It held a steady course for about 5 minutes. The main was being held firmly in place with both boom vangs (port and starboard attached). Unfortunately, I was heading away from the harbor entrance and had to turn back to the harbor since the storm was getting very close. I lowered the main and motored into the harbor. I intend to try the main only sailing this weekend and pay more attention to the setup and upwind performance. I swear I was pointing only at only 10-20 degrees with the secured main - hands off! This is a picture of the setup: http://www.yourcommunityweb.com/Monty15/preventer.htm