How to tell if a plugin is compatible with network enabled feature.

I need a rule of thumb for deciding when a plugin can be Network enabled. For some plugins it’s just about what I want to accomplish. Most of the plugins here at WPMUdev fall into that category.

But for other plugins in the wild I sometimes want to Network enable them but I’m never really sure if I’ll every run into problems. For this reason I tend to do a regular activation as a part of the a New Blog Template.

What I’m after is a way to tell if the plugin is capable of behaving well when Network Enabled.

Any thoughts?