Mine is just collecting dust. I have found there is always a better way to piece a unit than cutting out the individual triangles and then sewing them together. Say you were making a half square triangle block. Or a flying geese unit. You can get dies to cut such things. But then you are cutting and sewing each one together as opposed to using a method where you make 8 at a time.
What I do find I use mine for is border strips and binding strips.