I have Cole, longworth and donut chucks all homemade.
The Cole jaws are plywood and fit/screw on my SN2 chuck. I dont use them much except for small jobs ie lids finial etc.
The Longworths are 600mm and 300mm in dia made from Polycarb 10mm thick. One is one faceplate screwed to it and the other has a face plate ring attached.
The donuts of a similar size and a similar attachment as to the Longworths, all made from plywood.
Which do I prefer? Well each has it uses, benefits and limitations. The donuts have a greater capacity to handle a wider variety of shapes and forms over all the rest. But would be the most cumbersome to assemble and use.
Both the Cole and Longworth are basically for grabbing the rims of bowls and area capable of a wide variety of sizes. But light cuts only due to the design.
It pretty wells boils down to what your going to turn. If your doing small intricate bowls with lids and finials etc I would make a Cole setup. On the other hand if your doing salad bowls and the like. Then the Longworth are very versatile and suit this well.
The Donuts on the other hand can handle pretty much all of the above in a general sense with some mods etc. They do grip/hold best of all three and if your really keen hollowing can be done as well. But as I said the most cumbersome to set up etc.
But the up side is you can make the lot your self.