My first rotary cutter was the cheap variety JoAnn used to have on a slaes promotion for $1. I bought one and thought it was pretty good, so I went back and bought a dozen. Consider that I had a dozen new blades as well.
After a while I wanted one of the bent handle style and bought a Fiskar. I am still using it 6 years later. Recently I purchased an Olfa simply because I had a problem getting the old blades off the Fiskar. I later learned that a quick shot of WD-40 does the trick. Just let it set a few minutes.
I have cut and pieced my way through about 3 dozen quilts. I do not let my blades get so dull that I have to use a lot of effort. Therefore, I have no deep grooves in my mat. I have had 2 mats. With the first one I cut everything in the center before I realized it was full of fibers. (Don't forget to e-mail the manufacturers and tell them what you have found to be a problem. Fiskar is exceptionally understanding.) I bought a new mat, and turn it to use on the other side when trimming. I also learned that you can dry scrub the mat to clean out the fibers. I gave the old one to someone who wanted to experiment with cutting fleece for Linus blankets.
Remember it is cheaper to buy where they are sold at reasonable prices in quantity. We buy a stash of fabric, so why not have a stash of blades to make our cutting simpler. The service I use is:
http://www.houseofhanson.com/lpsharp.html
I would never use a box cutter. That is sheer folly to assume you won't have an accident if it slips. My daughter nearly lost the tip of her finger in art class with one of these objects. Please reconsider your intent.
June