I have been using straight conventional blades on my mowers. I recently purchased a new Xmark with a mulching deck. The blades are straight but have a variety of teeth where a normal 'high lift wing' would be. I think they are called "extreme mulching blade". I was hoping that the Mag-9000 would still work on those blades. I was planning on using the 'economic stimulus' check from the government to get one.