I actually have punted off a number of big stacks in recent years, but truthfully it's been more a product of suddenly running awful than anything else.
I probably should get a bit tighter after getting a big stack.
In general I don't fall into the trap playing too loose in Big O, as I know that's people's biggest leaks. On Day 1 of the Mixed Omaha, I was one of the tightest players at the table during the Big O portion.
I didn't play very well on Day 2 of the Mixed Omaha. I played too loose, and didn't read opponents' hands well enough to fold when beat. The day before, on Day 1, I did a much better job at both things. Just wasn't a good day for me. Wasn't even emotion or tilt. I was just off that day.
I played the PLO8 well and was very patient with things, and made a lot of good reads.