I've updated two of the draft keys to Malacothamnus available on my website if you'd like to try them out. One is for San Diego, Orange, and Riverside counties plus Baja California. The other is for Kern, Los Angeles, San Bernardino, and Ventura counties. Each of these keys expands the previous region covered, includes more taxa, and has hopefully improved couplets. Feedback is appreciated if you use these as that could improve the final key for the new Jepson treatment. Some other regional keys are also available and I plan to update them soon. Regions not yet covered will eventually make it there too.
Keys available here: http://keiriosity.com/malacothamnus/