Anyone hear that magnetic stripes are not a good idea because stones get under them and scratch the paint? And how do the MINI stripes hold up in general?

 

I've certainly HEARD that. Though I haven't personally had that problem. I have mag stripes on now - but they're on top of regular stripes, not the paint. I've heard bigger concerns about what they do to the finish when it rains - some folks are ultra-cautious to remove them before they get wet so no rain gets under them or they don't slip and scratch... and you must keep the backs of them and the paint underneath meticulously clean...