I'm using Marathon Plus's since a couple decades, and have had flats as many as before. 3 years ago I had a flat with a near brand new one, just a month mounted, due to a 15 mm sized stone with some sharper edges that cut/smashed itself through the rubber wall in one time (I could feel how the wheel was lifted up then down, only that at the moment I failed to recognize what happened), with the stone "held prison" inside the antileak compound, to then some 500 metres further notice the tires pressure drop. The tire, price 40 euro, was a write off, it was just too damaged.

Last thursday, I had a flat, a small leak, it took 8 km to notice the pressure drop (front wheel so less weight). There wasn't much to see at the surface just a small cut, but there was an entire hole inside the antileak compound and probably some object damaged the inner tube.

Yesterday I purchased a new Marathon Plus, but the moment I paid I already regretted it.
The thing is, before 2016, before this tyre was promoted as "unflattable", punctures>flats required nails either straight in, either in sidewall.
The color of the compound also changed then. I think the new one is easier for bigger objects to enter, maybe it's less dense, I dunno.

And they're a pain to replace. Today I replaced the damaged front wheel tyre with the new purchased tyre. It was a long time ago I did (I'm riding 2+ years with another bike with Schwalbes Super Moto X model), and it took me half an hour to just get one side of the tyre over the rim. The classic lifters all failed - they either broke, bent, or damaged the tyre enough to expose the steel cord (beware rust). In the end, I put a single lifter, just enough lifting the tyre to insert an arm of an inverted small combination plier, allowing enough force exertion to shift it sideways and flip more of the tyres edge over the rim.
To put it back on, one has to start pushing with two hands out air beginning at the valve ending at the opposed side. This way it was fairly easy to flip it over the rim.
And this was at home, sitting, no cold. The flat I had to replace along the road, forced me to damage the tyre in order to get it off.
Now that I found a method (the pliers) it may be easier a next time.
Why on earth they didn't make that steel cord / the diameter a bit bigger, I don't know. Maybe they want people to damage their tyres in order to sell more.


Due to the hefty price tag (also my fault, was forced to buy at a local dealer) I decided to try repair the damaged one with liquid rubber and also cover the exposed steel cord with it. I found 3 larger holes in the antileak compound under the rubber wall. I filled these first with molten (soldering iron) nylon thread. Shall see how this works out