I have been using 700x28 Specialized Armadillo tires for almost 7 years on my commuter. They come in a variety of sizes, including 700x23. I have not tried any other flat resistant tires and thus cannot do any kind of relative comparison.

Fixing a flat on my commute is just about the last thing that I want to do. The Armadillos are not perfect. I still get flats, but the flats are usually slow leaks that I do not notice until the next morning. Although thorns are not a particular problem in my locale, I have had pieces of glass and thin metal wires (probably from damaged steel belted auto tires) that work themselves through the tire into the tube. Doing a better job checking what might be embedded in the outer surface of the tire and removing it promptly would probably help.

I get about an average of about 2500 miles per tire - a little more on the front and a little less on the back. They are not cheap and can only be bought at Specialized dealers, so I keep an eye on prices and buy a couple when I see them on sale.