I have three different makes, but the one I use all the time is the Olfa that shuts (or goes into safety mode) when you put it down. This is the safest one for me, because I am inclined to forget to put the safety catch on with the others. With my Olfa, I know it is safe the minute it is out of my hand, because the blade is only in operation when I am squeezing the handle. (You can also lock it in the safety position, if you have children around) Worth any extra money to me, compared to cheaper alternatives.