I am with Arlin and amazed they last. I go through a lot of blades! Enough I buy 8-10 at a time. I had them break suddenly. I have have them develop a crack in the gully and start to 'thump' as I am sawing. I have had them last 30 minutes and break. Most last till they are just dull from the plywood. Breaking is just part of it, it happens so keep spares.
I have found how much a boat is used is inversely related to how much it weighs.
Kudzu Craft Lightweight kayaks
Kudzu Craft Lightweight kayaks