I have been using Olson Flex Back blades for 2 years and have found them to be quite durable. I use them until there are no more teeth on the blade and I have to throw the blade away. The only reason I didn't rate it a 5 is that the blade sometimes breaks without much use. Not often, but still happens. I use blades for inlaid detail and do a lot of backing with no problems. I also use blades for very hard woods as well as for softer woods. This is a good blade and I recommend it for most uses.