I found I use less fabric when using the Go. I don't have any bad or miss cuts. I mark around the dies 1/4" with a black Sharpie and that is my fabric guide. So I have 1/4" waste, less then squaring up the fabric to cut with a rotary cutter after every few cuts. The cutting mats last me a long time because I buy several and use different sizes on dies so the cutting isn't in the same spot all the time. If the mat will fit over your cutting blade it's fine to use it. You don't have to cover the whole die. I cut paper/card templates, fusible, oil cloth, anything my scissor or rotary cutter will cut I can use the Go to cut. Using common sense the Go has given me perfect cuts, saves time, and saves fabric. The downside is I have very few scraps to add to my scrap pile.