I had the Schwalbe Green Guard in a 42-622 for my MTB-Hybrid. No flats in four years and about 8K miles before swapping for Marathon Supremes (no longer available). I ran over all kinds of debris including broken glass. The Green Guards do come in a 25mm. They are a robust tire but you will suffer a weight and rotational inertia penalty but I did not care as I ride for recreation only.