I had a 26' Chrysler that was pretty solid in my opinion. A storm was rolling in when we were headed to the slip one time, and the wind changed direction by 30 degrees and upped it's speed a LOT (not sure how much, but it's still the biggest gust I've seen on Lake Lanier).
When the direction and wind speed changed we were sailing pretty close to the wind on a starboard tack, with a 130% genoa and the main up.
Then BAM it hit us directly from the side and the top of my mast was _maybe_ 12' above the water, and just as quick, we were up again, but it was a very gusty wind and I let both sails go, brought them down and we motored in.
That keel will do a LOT to keep your boat from going all the way over.
I'm pretty sure I would not test it too hard though, as Denise suggested. She may be right, but I'd check the sea ratings of the boat and search for a forum dedicated to your make/model and learn from their experiences.
Have fun though, sounds like a fun boat. You may want to see if you can borrow/rent a smaller boat sometime. You can learn a lot about wind and sail trimming on them pretty quickly.
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