Iv'e been using a simple Point7 system with a Chinook clew pulley wheel. Basic, simple and reliable. I only use it one side and it works fine for me. The Chinook pulley wheel allowes for zero friction, keeps thing centralised and increases the threading options. Unifibre also do a very similar basic adjustable outhaul, Iv'e just ordered one to see how it goes.
I think I might move the cam cleat closer to me..if the re threading has put the boom adjustment back to normal ( which means I can move it one hole in) and I move the cleat inboard by the same as the boom ext amount hopefully everything will stay as is?
I set up my boom today using Sailquiks method (thank you). Rigged up on the grass but the wind never came. I suppose proof will be on the water, but I was just wondering, we go to all the trouble of getting a stiff carbon boom and then introduce a lot of slop into the system. Maybe we would be faster downwind with no clew-boom end gap? (and put up with the extra effort going upwind)
1st use yesterday.
I moved the cam cleat closer to my backhand and everything worked well with the 7.8m but it may need adjusting for the 6m.
Loved it! 
I was overpowered and underfinned ( for me) for a lot of the session 7.8m - 89ltre falcon + 19cm delta so I pulled it on tight to get upwind then as Larko said ' bagged the s..t out of it ' to go off the wind. Definitely gave me more power off the wind.
I even remembered to pull it on pre gybe 
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Heaps more user friendly than the sailworks one sided one I had ( although the one I had was an early model and didn't have the little pulley section inserted in it).
I was letting it right off as I was reaching across just before the bearaway.. Is that where you let it off or later? It was just convenient then..
Why have they not made on the fly adjustable booms? I've thought of designs 20 years ago for adjustable booms.
Any manufacturers pm me and we can set up shop.
tested my one sided setup at Liptons a couple of weeks ago. Worked ok, but clamp slipped a bit on the boom arm. I took it off because I decided that I couldn't be bothered with the fussing around. Still, I can always put it on again if I change my mind. It could be useful somewhere like Fangy's where there are quite long upwind and downwind runs
