Our Westpaw design zogoflex toys last pretty long (months) before they are destroyed, and they will replace the first destroyed toy for free. In fact, Revy just finally chewed the Bumi in half yesterday after having it since Christmas.
Revy destroys most of her toys within 24 hours, so the Zogoflex ones are like magic. Also- the Chewber frisbee has lasted quite a long time, too, but she doesn't really use it for chewing.
Revy (Zanka vom Blackgold Pen): Female GSD born March 2013
Sweetie: Female black cat, born 2004
Plus a husband and a couple of teenagers