When I built my house about 8-9 years ago, I had my sprinkler system designed by a irrigation specialist (some on the board will know whom I'm talking about). Instead of spray heads, we went with MP rotators because they are more water efficient. They spray larger droplets so less wind and evaporation loss. The drawback is that they don't put out the volume of water that the spray heads do. I think they run about 0.4" per hour. I've also upgraded the controller a couple of times to the most advanced available. It factors in soil absorption capacity, type of plant, evaporation rates etc., and then cycles through the zones to prevent runoff and maximize absorption. I think I'm the most efficient I can be with hybrid bermuda (TexTurf 10). That said, we are limited to watering once a week and my system will run 9 hours through 13 zones, so the grass is surviving in areas and struggling in others as my ground is heavy clay. We also installed a flow meter a couple of months ago and the system runs through right at 4,500 gallons each week
The other thing that we did, and I would recommend this to anyone that is building or putting a sprinkler system in, is to install a drip irrigation system for the slab. When the system was installed, a trench was dug 2 feet deep and about 12 to 18 inches out from the slab. One drip line was laid in the trench and then a foot of soil was added. A second drip line was added with a soil sensor, so that the slab is automatically watered whenever the minimum moisture baseline is reached. Right now, the slab is being watered twice a week for an hour each time (about 380 gallons each time). We are on some of the worst clay in the Central Texas area and, so far (knock on wood), we haven't had any issues and we have monster cracks outside of the "good grass" area with some that are 3-4 inches across and who knows how deep.
All of that said, the shitastic private water company that supplies the water can't provide the volume to run the sprinkler system (it can take 80 seconds to fill a 5 gallon bucket with the faucet wide open, so around 4 gallons a minute). I've had to install a 2,500 gallon tank with a water pressure activated pump to get the sprinkler system to work. So if you are outside of city water supply, make sure you are aware of both the pressure and volume that the water provider actually supplies and the effect that can have on your system.