Without the Cobra SA32E 13 inch electric scarifier, I would not have been able to remove the thick layer of moss that was slowly killing the grass in my lawns. After changing the barrel with the blades on, the setup as delivered, to the one with the wire tines, that comes in the box, and setting the height to the highest, on first starting to scarify my lawn I thought I had a problem with it. The moss was so thick, that the supplied catcher bag, that fits on the back, same thing as a lawnmower, was useless, and it is useless, no where big enough to cope with even a small job, I never used it again, and resorted to raking off the scarified moss by hand. Apart from the useless collection bag, that seemed to be the only thing wrong with the machine, it did a really good job. I’m quite sure I will never use the machine with the blades fitted, and would have preferred two sets of tines, one as a spare. I think if you used the blades, I believe are for aerating, on your lawn, it would chop it up. The only other thing I thought was very poor, is the handbook that came with the machine. OK if you have 20/20 vision, I don’t, the printing was very small, so were the diagrams. The booklet was poorly laid out, wasting a lot of space that could have been used to make the text and diagrams bigger and easier to read. I do recommend the machine itself though, as I am in my 80’s, and I could not have done the work it did, by hand.