My first taste of Kei at Exotica in Vista, CA was a surprise. Refreshing sweet/acid with a touch of something almost vegetable. Cucumber? I'm not great with describing flavors. I loved it. Immediately bought his female 'Silber' and a male. They've been in the ground for many years now and I just got a few flowers. Makes me a bit suspicious about their clonality.
The botanic gardens also has several trees and one of them with fruit about as good as the Silber I tried. Only tasted once though.
It air-layers readily and I have 3 airlayered plants of the Silber.
I have a couple Silber seedlings and a dozen of the SDBG seedlings. Just planted a hedge out actually with a mix of all 3.
the seeds sprout readily and are very tough. Growth in a pot has been slow for me.