I'll second the Schwalbe Marathon Plus. No flats in about four years and 10,000 miles. In contrast, my Vredstein Spider tires, with Tuffies, would flat every month / 200 miles on the same route. They also have lower rolling resistance and a better ride than the Vredsteins.

I suppose one could use Tuffies with the Marthon Plus if you are still getting flats. I don't.

Paul