I would not trust that person unless they looked exactly like me and had a pair of futuristic goggles and a laser gun for me. Because if they don't look exactly like me (a different hair style is allowed) they're probably not me and it's BS, and if they do, but don't have a pair of goggles and a laser gun for me, I'm going to die if I follow them. Because they will have gotten the equipment from the future me that came back for them, I'm going to have to get the equipment from the future me that has come back for me (I know this because the future me has one set of goggles and gun and I would treasure that s***), and the next present me will be retrieving his equipment from my corpse, ie. I'm going to die in less than 9 minutes. If he has two sets, then there's a possibility he only needed me for a little while, then he continues living his future life 9 minutes ahead of me and I get present me who is 9 minutes behind me, we do whatever I was needed for, and I continue living my life in the time stream I started in.
That said, I would probably not have the luxury of forethought, so if they looked like me I'd follow and if they didn't I might anyway out of curiosity or more likely wouldn't because I have somewhere to go.