Product review (4 stars): Glad to have these back.
Having beaten up a set of aluminum gap caps over a decade, I opted for the silicone. Hated them.  I'm so glad to have metal ones again. They aren't sticky feeling like the silicone, don't curl up when the edges are bumped, and do a much better job.  These are really nice, though a little wider than my old ones, which is why I give 4, rather than 5 stars. It is just a personal thing.