My vote is for the 642 as well. I carry a Ruger SP101 every day and a S&W 340 SC when my back is hurting. In my opinion in a SHTF situation I want simple - point & shoot. I think, at least in my case, I would fumble with sliding off a safety, and in a failure-to-fire situation - pulling the trigger again beats the heck out of rack-tap-n-slide in a semi. I also don't think it likely that I will be in a situation where I need more than 5 shots to resolve it. Just my 2c worth