Tubes and Tires, the never ending questions

I ride twice week, about 40-50 miles each day.
Ride speeds from 8 mph up some hills, to 35 miles an hour down some hills, with an average of about 15 mph.

I've tried many tires and tubes. We just bought some tires a year ago designed to handle road debris.
A year later they are all chewed up.

The area we ride has some rough road and a fair amount of debris, sewer grates and othe things that we sometimes ride over.

A little extra weight is fine, if I can find things that last.

Input would be greatly appreciated.

More...
Tube problems...Stem breakage and puncture resistence.

Size of tire would help, some sizes have limited offerings. By your info you ride
4000 to 5000mi/year, most rear tires are not going to last more than that, and
actually 2000mi is good mileage for a rear tire. You can expect to go through
1 to 4 tires per year. 30-50% of tires fail because of cuts to the tread or side
wall, the rest wear out. Steve

For the tubes/stems, are you using good quality rim tape/strips? Do the valve holes match the stem's size? Any sharp edges, etc?

What size tires are you running? What's the rider weight and road conditions?

obviously the questions about tire size are important to whats available. If you can find Specialized Armadillo's that fit your bike try them! I've had great sucess with them on my mountain bike riding around town - 1 flat in a year and a half! If you're tires will accept shrader valves you should try slime inside the tubes - specialized makes a good product, and the "slime" brand works well too. It's good for punctures because you just pull the thron, nail or whatever and reinflate. It's also my understanding that continental makes a presta tube that you can take the valve stem off and insert slime in the tube.