I bought a dozen split rings 2 years ago in order to give them a try out.
I, as some of the rest of you, have had them open when pulling with my cable stake puller.
However, that is not my real concern. Maybe I am not connecting them properly, but it seems to me that they are setting you up for theft. It's too easy to disconnect the trap from the cable stake. In areas with high trap theft, the thieves might come prepared with tools. In my area the occasional thief, or hunter, who takes my traps , does not carry tools. The cable stakes are too hard for them to pull, and there are more secure ways to attach the traps. The split rings make stealing a trap too easy.