I got the Testrite Safety Edge a couple of days ago, and while a bit pricey it does a good job. I think the only complaint is the bottom rubber can pick up cardstock scrap pieces, so every so often you need to clean it off. Other than that I really like it.

You might have some folks call dexterity. Me, I trip over my own two feet at least once a week.

Quick tip that worked well for me last night. I had a new steel ruler and it was just a bit slippery on the paper leading to shifts or excess pressure and tired hands. After a few minutes in the garage trying to find something thin but grippy I ended up grabbing my sander and running that over the surface of the rule with some 120 grit. It worked great, added zero thickness, and was free. Much happier now that I have a grippy steel rule that sits right on the paper.

And I found this monster (tempting), but I got the much smaller version. But very cool! It's non-slip and both sides facilitate cutting. One is flat while the other is inclined.

That is a beast!

I was using a small (ie thin semi flexible) steel ruler that was 12 inches in length that I had purchased back in '95 for my drafting class that I took my freshman year of high school.

I now use the Silver 12 inch Alumicutter ruler

that Chris (Mel Ebbles) was selling on his old site, I got mine in the Starter Kit he was offering. I love it, and am thinking of getting an 18 inch one and a 48 inch one (the 48 inch one will be used for when I am cutting mats for photographs I am framing).