The i-9 is my favorite inflatable, and sailing it, IMO, is fun and relatively easy. The inflatables tend to have more weather helm than the plastic Hobies, but you can mitigate most of that with your large rudder and raking your sail forward. In light wind it's not an issue anyway. On a broad reach or running, you can slip an extra batton in the foot seam to form a "boombat" that will give the sail better shape. I'll try to post a picture of it next week.
Here's a brief sailing review from a few years back:
"The boat is so small, the Hobie sail finally looks proportional! Sailing is a blast! The wind picked up and was gusting to about 20 MPH. The boat never felt unstable -- the sail just heeled over by itself (hull flex) to dump wind. The boat got up to 4.4 MPH without any help from the fins. The ride was much drier than with the standard boats. Even with the mast raked forward and the large sailing rudder there was a significant weather helm with high wind -- at times hard to control. The boat tracked surprisingly well beating into the wind with Turbofins serving as daggerboards."Daft really enjoys his sail and I think you will find it not only fin, but hybrid propulsion (pedaling and sailiing) will scoot you around pretty well!