For me, I think it depends on the date. I would need more information on who the guy is you're considering going on lunch date with before saying if that's safe or not. If it's someone you know relatively well that you've decided to go on a lunch date with to get to know more, I'd say it's pretty safe. If its a new acquaintence, and someone you don't know, I wouldn't let them pick you up at work at all, but someplace more remote and unrevealing about your employer. Then again I probably wouldn't go on a date with someone that I didn't know well enough to feel safe with anyway. But that's just me.