I once had that variegated Agave attenuata (a striped cultivar, though) in my garden as well. Much as I liked it, I won't replace it because it is very vulnerable to frost. We had a very bad frost in the San Fernando Valley, several days in a row back in the early 2000s. All the leaves of that plant were killed back to the crown, but wanting that plant so much, I kept it to see if it would come back. It did, but without any variegated leaves. It lived out its brief, unvariegated, weak, discouraged life and expired a few years later.  

I really like growing the uncommon but not really "rare" sea onion, Urginea maritima, and I have 2 distinct varieties: one acquired from a catalog, the other purchased at SoCalHort meeting from Joan Citron. They are named the same, but there are differences between them. My catalog plant has narrower, more wavy-edged leaves, and Joan's blooms sooner. I grow them next to paving in full sun.