I don't know if the Marathons come in a kevlar bead as well as a wire bead but if so, you might try them with a kevlar bead when you replace them. Kevlar bead tires mount much easier than wire bead. Rain causes all sorts of particles to stick to the tire and flats are much more common in rainy conditions. No question about that. Gatorskins are my go to tire for flat resistance but they don't hold a candle to the Marathon Plus or other serious tires like Armadillos. I don't know much about the serious flat proof tires but there's a real price to pay, as you know, when you get more and more flat proof. I watch the road carefully and if I think I've ridden over trash/glass I stop and do a quick brush-off with my hand. Better to do that 20 times for 30sec than a single change of tire.