There are dozens of ways to cut materials with varying degrees of success. If you already use the standard ones, especially a sawzall with a full set of blades you might feel you have your bases covered.  But this Diamond cutting rim attached to a small angle grinder like the DEWALT D28402K makes life so much easier.  I purchased one for a bathroom renovation and steam room project and needed something that would cut everything from cement board to concrete to wire mesh. This blade exceeded all my expectations.  The cuts are straight and true and it eats through everything like a hot knife through butter. I found myself reaching for it to make quick cuts in sometimes cramped places and in seconds the job was done.  It did some cuts that would have been impossible using anything else.  If you're a DIYer you might not have considered owning a small angle grinder or a diamond saw blade in the past.  But once you've used one like this Dewalt, you'll be very happy you added it to your tool arsenal.