So, how to compare streaming audio between KS9s and Jabras:
First, I’m not an audiophile, by any means. So, my first metric for streaming audio is how “natural” the speaker (think, narrator of an audiobook or podcast) sounds, compared to how I remember them over the past decade or so. Probably a better benchmark for me is the “sound” of a voice with which I have decades of familiarity, including in person. In that regard, streaming an HD voice telephone connection directly into my hearing aids (KS9s) was a revelation. As was facetiming with my daughter and grandson on a Macbook, using the KS9 as the “headset”. Very accurate and comprehensible, similar to listening in person, and so much better than using Macbook speakers. So far (and the fitter made some changes yesterday), the Jabras seem less accurate than the KS9s according to this metric (HD telephone connections). Plus, the Jabras don’t directly accept streaming from my 2021 Macbook Air.
As to music - my Pixel 4a will pair with the Jabras and the KS9s simultaneously, so I can fairly easily do a-b comparisons. Unfortunately, Spotify on the 4a doesn’t seem to want to recognize the Jabras as Bluetooth output devices (or I haven’t figured out how to get that to work), so I’m working with just a couple of music files uploaded to my phone so far. Jabras sound “thin”; KS9s are more “full”, but maybe a bit “boomy”. 
I think much of this had to do with programming; I have a post comparing the KS9 fit to the Jabra initial fit (from Target and Resound Smart Fit), which shows some big (to me) differences. Fitting comparison for KS9 and Jabra Enhance (Resound One)
I need to update that post with the changes made yesterday at Costco.
As to speech understanding, performance in live performance theater venues (important to me), etc. - wow, that’s a work in progress. Went to a performance at the outdoor theater tonight here in Ashland and was toggling settings for Jabras and KS9s and swapping the devices in my ears. It’s exhausting. They’re different. “Better” is hard to discern. I think the Jabra programming can be improved (and so could the KS9s for that matter).