...latest version of SuperDuper (version 2.7.5(v. 95)) runs but for some reason I was not able to produce a bootable clone using it and I have not taken time to troubleshoot the issue....
Here's Jason Snell's July 9 report on SuperDuper's v2.7.5 status with El Capitan:
Six Colors Blog Here's the Sept 13 update from Shirt-Pocket's Blog about compatibility:
SuperDuper status