California Lilacs, or Ceanothus, are some of our most fragrant and colorful shrubs here in California. They are also evergreen and very drought tolerant.
The myth of Ceanothus being short lived is primarily spread by incompetent gardeners that insist on drip irrigation, summer water and soil amendments. California native plants hate all three. Expect a 20-25 year life from your Ceanothus in most gardens. We have many Mountain Lilacs in the ground here that still look good after thirty years.
Ceanothus are notorious for being loved by deer. However, this is not entirely true. Without water or fertilizing a Ceanothus looks much less appetizing to a deer. Some species are still viewed as candy in areas where deer populations are high. But many are OK in low or medium deer areas. If you have high deer problems stick with your local Ceanothus species and whatever you do, don't water!