Completely ignoring color or other factors,
Which one is better for rebloom and fragrance?
I would think Yolanda problematical in zone 10.
I had her twice. With a north exposure and afternoon shade, she was fine. At the next house, with east exposure and in town water restrictions, she hardly grew at all.
I don't know anything about JI.
I'm guessing you would appreciate someone's first hand experience - I wish i had bought Yolande d'Aragon years ago so I could tell you, but it kept selling out before I could buy one. That's a good sign.
Tried to do some research for you; it seems YDA would come out ahead with fragrance, although I couldn't find anywhere that would say what it smells like. It seems years ago I heard it smells like raspberries but that may be mistaken for another rose. I would love to know...
Paul Barden says Janet smells citrusy rose as you probably already discovered. He also remarked that Janet blooms in "generous flushes" which may win out over YDA in that respect.
When I can't decide one or the other, I abandon them both out of frustration!