I would think riding it out with the boat on it's side would be the best. The likelihood of keeping it upright is slim to none, but I've only ridden out wind like that for ten minutes on a smaller lake. So no big waves. The wind was reported to be 60mph, but I don't believe it was actually that high where I was either.
I do think that no matter how many times you run a scenario through your head, the reality will always be different. Location, severity of the weather, and who you are with, then throw whatever level of exhaustion you've got going on top of all that. Any level of preparedness certainly won't hurt though. What I'm getting at, is there isn't a set answer, just the hindsight of what should've been done differently.
While I have no direct evidence, I would be a little concerned that the boat might self-right if you leave it on it's side. Frankly, I was pretty concerned about it when we flipped in what was gusting to 36knots during a steeplechase several years ago. It only required a slight flinch to right it. Maybe if you can sit on the mast and hold it down? (that is, if you don't lose the boat in the process as it will be flying through the water even on its side)
