To me this isn't that complicated. Read body language and if you have any doubt don't say it. If you know you're awkward and come off creepy (which men should know about themselves) don't say it. This isn't rocket science here. Let's also acknowledge the facts: majority of the time a man does have some small ulterior motive. Almost. Always. It may be slight, but it's there. And today's society is different. People are waiting to find offense. Safe guideline, if you don't have a rapport with her, don't comment on her.