That's a mixed bag of opinions. For some, the rag joint does involve dampening road vibrations so is good for lower performance cruisers etc, but on the other hand the jeep u-joints do offer more responsiveness and better feel for the road.
Either way, if the boot is that trashed, the rag joint isn't that far behind it. There's 3 options, really. Replace just the rag, which is a pain and involves grinding, heat and air-tools, or replace the entire shaft with a new rag setup, or replace it with the jeep upgrade (new or used). Just 2 nuts, one on each end, and a prybar will generally get 'er done.
My upgrade was a new jeep shaft, but the idiots had spot-stamped it solid in 2 places, so that involved drilling out the stamps so it would compress. No big deal, really.