I opt out 100% of the time. Instead of me just feeling violated (by going through the scanner) I think it's important that the TSA feels violated too. Most of the time the person doing the opt-out is humiliated as well. I also think it's important for Americans to see it.
The TSA at LAX really tries to talk me out of opting out. Maybe that's why.
I've been given the intimidation routine ("You know this means I'm going to touch your private areas," and "Do I need to call a supervisor?") and the downplay routine ("it'll only take 3 seconds and it's completely safe"). It's always in that order. It's always the same; send the bully then send the supervisor. It take 5 minutes to go through that. I've taken to simply standing in silence with my arms outstretched and legs apart.
I always refuse the private room as well, not so much because of the witnesses but since it seems to me to be a much more efficient protest to have American citizens see a guest in their country being molested by their security personnel.
Flying out of SFO (where they have MMW machines, at least in the terminals I use), there's another person opting out about half the time. If I get a chance, I'll ask them why. It's almost always a matter of principle, as it is with me.
