I have a 6x24 Olfa Frosted, 6x24 Omnigrid with the yellow lines, and a 8.5 x 24.5 Creative Grids. At one time, I had a Quilter's Rule 6x24 with the raised ridges on the bottom.
Of the above 4, I like the Olfa Frosted the best, and actively dislike the Quilter's Rule with the raised ridges.
For the majority of the things I cut, I find the 8.5 x 24.5 ruler a bit unwieldy - I also find that I have to "pay very close attention" to what I am doing when I use a Creative Grids ruler.
There are two rulers that I use a lot - a 3x18 Omnigrid ruler that has a 1/8 inch grid, and a 4x8 Omnigrid ruler that has a 1/8 inch grid.
But because I am a bit scattered, I tend to use whichever ruler I find - except for the Quilter's Rule ones - I wore an arc into the sides of them and they were put in the trash.