I planted Cordifolia in 2012. I’m not sure when I first got fruit, but I know I was getting it by the time I wrote the below post in 2018, so it was 6 years or less.
Issai produces fruit almost immediately (I think some in the 1st/2nd year for me), so if early production is what you are looking for,
Mine are in a pretty decent spot- most of the shading the get is self-shading from rampant growth. They may lose a small amount of early morning and late afternoon as most places a lot of neighbors do, but get sun for most of the day. Not quite as perfect as the spots I have some jujubes in where the ground slopes away to the South & West, with a wide driveway to the East so they get all but a few minutes of sun.
Even so, Ken’s Red has taken 10 years. I also grafted Cordifolia in a less ideal (but not bad) spot in 2020. It may have had a few fruit last year, but it has quite a few this year. Much more than the less-pollinated but 10 year old vine.
I think you’ve mentioned not liking many hardy kiwi’s because of an off flavor. I’m not sure if I taste exactly the same thing, but some kiwi taste good at first, but I quickly get sick of them (even when they have high brix, which they don’t always). This includes Issai, Geneva, and Chico/Jumbo. Jury is out on Fortyniner, but mostly because it produces very few fruit from a massive tangle of vine.
Cordifolia and Rossana both seem to be very palatable, which was why I grafted more Cordifolia and trained the older one to cover almost 50 feet of trellis space (from the vine, there are 4 supports spreading out (covering about 120-140 degrees). Regrettably the male wasn’t ready to pollinate the massive vine this year.