I did this. Although it wasn't 50 percent less, but I did take a pay cut to take a different job that I considered my dream job. So I would say yes, I would probably do it again.
All the money in the world can't buy happiness. I'd rather be happy doing what I love to do than be miserable every day. I guess its all in perspective.
On the job stress causes health problems, I think I would rather be happy.