Weight and ease of transport...and often priceWhat's the difference between a folding tyre and a non folding tyre?
Also, are these any good:
https://www.wiggle.co.uk/continental-grand-prix-5000-tyre/
Another vote for Schwalbe Marathon Plus ..... but had you also considered Slime (or similar) self-healing tubes too? I find it best to double up.
As a 300lb cyclist I've done nearly 24,000 miles in the last 10 1/2 years with only one puncture out on the road ..... and I blame my own carelessness for that one. Peace of mind at the cost of a few ounces of extra weight.