Review on Enhanced Performance: Amana Tool 46180 K Spektra Compression – Unleashing Optimum Cutting Efficiency by David Hill

As others have said, these compression bits can easily break if you're not careful. I broke the first one I had, but none have broken since. I cut 1/2" birch plywood with them and found that they tarnish fairly quickly given the cost and the "super hard" finish. Once they dull they produce enough pauses as the bit transitions from vertical to down. I will try the cheaper holzy and whiteside compression bits to see how they work.