My parents' cats wear the stretch-away kind (like this: http://www.petsmart.com/product/inde...ductId=3195379
)and have no problems with them, though the elastic bit tends to break a lot more frequently than the break-away buckle kind I use. In the past they have both been able to remove their collars by snagging them on something and pulling their head free - though once it was by breaking the elastic bit, rather than just stretching it.
My boys intentionally remove that kind of collar and chew on the end of the fabric that goes through the metal buckle, so they wear the breakaway type. I just ordered some ragtime collars for my boys and am awaiting arrival (those have the breakaway buckle also).