So the difficulty here is the message preview. Clicking on the message in the message list, is going to display something in the preview pane. That might or might not include remote content depending on your settings. But you can turn that off.
The question then is, if that pane is not visible, will it have the same affect, i.e. retrieving content? Or will you be able to scan the message list of your Junk for those odd hams without the chance of unexpected connects to the Internet.
My testing says it is safe either way.
It does require some testing by eM Client, but for them to do that, they need a sample that ignores the privacy settings. Maybe Scott will get another. 