I did go over via Otay last night. It was not to go to the Zona for pleasure but to help a friend who lives there. She paid a Libre taxi 200 pesos for ride ti Zona Norte area, so HK should be same.
Going home I decided to use Uber. It was 145 pesos and I handed the driver 40 pesos as a tip.
It was close to 30 minutes. As someone who crosses 5-15 times a month, every month for over a year, San Ysidro is the way. If you really hate the line, save your taxi money and buy a 6 month VISA for about $30.3 weekends and you've broken even and saved hours.
