My current favorite rulers are the ones by Olfa.
I like the frosted look, the measurement lines are easy to follow.
The ones I don't like as much any more:
Quilter's Rule - the ones with the raised lines on the bottom - the lines are very thick
I had one with a lip - I gave it away because it annoyed me
And then there were a couple that the markings were waaaaay off - just because it's printed on the ruler, that is no guarantee that it is accurate - I don't want to state the names, because I don't remember -for sure - what they were.