Pea Sized Gravel - The most common but rocks fly everywhere when dogs run and many dog love to eat the rocks. Rocks are very dusty and dogs go home really dirty.
Wood chips - They hold smell (think how many dogs go to the bathroom on them everyday). You can't clean them because cleaning solution soaks into the wood chips. Plus they smell really bad when they are wet.
Regular grass - Pretty obvious why this is not a good option.. You can never clean it, dogs get dirty and muddy anytime there is rain or you play with the hose and grass never grows because dogs are always running on it.
We LOVE our recycled turf, it comes from an old sports stadium and fits in well with us trying to be a "green" doggy daycare. The turf hold up great and we just wanted to freshen up the look of what we had outside. When the guys were almost done installing the turf, they realized someone had mis-measured, so we did not have enough to do the whole area. So there is a small corner that is not finished yet. I guess everyone learned the lesson of Measure 10 times and order 1 time :) Not big deal, it should be 100% finished by the end of the week. I was out there when the dogs first saw the new turf today and they LOVED it. I am so glad we went with this option 2 years ago because I could not imagine sending home really muddy, or super dirty dogs.
Have a good night.