I wouldn't like to use the CLX 27 all day. I just keep that for three story work. My suggestion is to get at least two poles (if your budget allows it). The SLX 18 foot is perfect for the vast majority of my domestic work, and the CLX 27 for three story stuff.
What I'm saying is, is get a top quality pole for your bread 'n' butter work; the stuff you do most of the time, and go cheap on the pole which you'll use the least; which will be your longer one.