In addition to waves and frestyle, most PWA sailors use a waist harness for slalom. I switched last year and I found the waist harness much better for overall control of the board. It also makes hooking in/out of the harness easier, and therefore you come into the jibe with no hassle from the harness, and it helped planing, probably because it is easier to keep a correct stance, or maybe is the pull that puts less weight on the tail.
Only limitation I can see is with big sails, I used it up to 7.3, not yet with a 8.0.
Last edited by davide; 18th February 2010 at 10:53 PM.