Martelli has been running a 50% off sale on their mats over Mothers Day weekend. Sale ends today
http://www.martellinotions.com
with macular degeneration which affects the ability to see colors correctly, I found that the green Olfa mats, which I've had for years blend with some of the colors I cut. I use rulers and not the lines on the mats. The yellow and purple mats give me more choices when cutting