I've had a 8" jolly ball in the yard for a month. It's showing some wear and tear, but part of that is my fault. My pitbull, Beau's favorite game is for me to squish the ball and jam it under the deck. He'll sit patiently until the ball is puffed up again (love that feature) and then he'll spend a few minutes ferociously pulling it out. After a few fierce headshakes, he'll drop it at my feet and go sit by the deck again. This could be why one side of the handle will likely break within a week or two. Great toy!
My golden LOVES his Jolly Ball! He doesn't chew it up but enjoys carrying it around & tackling it on the ground. He also likes to play keepaway with it. It has worn a bit at the handle but it's probably 5 years old. He has tons of tennis balls in the yard which are the target of his chewing (ripping off the covers is a specialty). His Jolly Ball is a favorite.
I had the horse Jolly Ball in the past and that is made of heavier duty materials. After one play and fetch session with this one, the handle is already halfway bitten through. They are right that it doesn't pop, but I am not impressed by the durability of this toy. I would not purchase it again, though I would recommend the horse version of the Jolly Ball.