I already purchased flossies in bulk before and was also worried if the guys would get tired of it. What I would do is vary it every other day -give them the bully sticks on day, take it away and give chicken strips,take it away and give flossie, etc. That kept the excitement going...
Here is a picture as well as description of a flossie...my dogs just love, love, love them.
http://www.amazon.com/gp/product/B00...lance&n=284507