This is probably the most fundamental scrapbooking product I own... I organized my table top in my studio around this mat :) I use this mat for all my layouts and projects, even on the GO. And it's not only great for cutting, but it also acts as protection for my furniture... it catches all the paint splatter, adhesive, glitter and other messy stuff. I love it and highly recommend it.
This is a great mat. I use it not only for cutting but for positioning my pages when I am not doing things on angles. Because I can put the 12 x 12 page within the measurements exactly, it helps gets things center. The retractable knife is great for a household with kids so if I forget to put it away, my step daughter won't grab it and cut herself.
I use this for every project!! I love it... the ruler is great, and i love using an exacto knife to cut paper on the self-healing mat!! Mine has so much glue, paint and adhesive on it, that soon i will have to buy another to replace it!! I never start a project without laying out my EK mat, ruler an knife first!