A couple things. First, one more link to the list codeman gave. Try
www.sea-doo.net There is a message board on there with lots of awesome information. Green hulk is a member there.
Secondly, I don't have OPAS on my ski, but if I did I would disable, based on what I have read. There are no benefits to having it unless you are a novice rider. I would guesstimate that well over 50% of the people on Sea-Doo.net have eliminated OPAS and have no regrets in doing so. Most of the comments I have seen are similar to what codeman has said above.