I use one for my M16. For the field it is great as it is more compact a long cleaning rod. I like it more so the segmented cleaning rods as those things always seem to be breaking.
One thing I have found out: Be careful how much patch you try to pull through. The handle on my Otis has been bent many times trying to pull a patch through that was too tight. With the Otis kit it is way too easy to try to pull too much patch through the barrel. And if you do get it stuck, it's a real pain in the neck to get out since it has to be pushed all the way through with a rod, as you can't push with the cable and you certainly can't get a rod down from the muzzle end with the cable in the way. And yes, I got a patch stuck so bad 1 inch past the chamber that the handle bent into a u-shape and required a Leatherman, an assistant, and the side of a 5-ton truck to pull through.
The problem with getting patches stuck is that you pull it from the chamber, which is nice and big but tapers down until it's too tight. With a rod, you simply back it out, but with a cable, there really isn't any reverse.
The end result is that they work, but you just need to be careful.