The longest lasting treat are elk or Deer antlers. A few companies make these, we have a bunch from Ziwi Peaks. Once you get a dog started on these, you'll save a ton of money in the long run, some times you might have to soak it in chicken broth to get them started. Then once they know they are suppose to chew it, it's a fantastic treat.
Himalayians are great also - some dogs go through them fast, some take a while.
The thickest bully stick, I ever seen have been the "Bravo Bully Sticks" they are 12 Inches long, but super thick. Out of stock on them currently, until wednesday.
The free range ones are much thinner, but they are priced much cheaper, every time we get the small packages of 4 in, they are always sold out within a few days.
If anyone wants to try wizzlers, from Merrick or the deer antlers. Use coupon code "YTpromo", which will make it 25% off, offer will expire Dec 15, 2008 or while supplies last.
Merrick Wizzlers - Luke's All Natural Pet Food Ziwi Peak Deer Antler - Luke's All Natural Pet Food