I'll try to give you something of an answer. First, I haven't heard the Hybrid JR but I do own the Hybrid MLT so I'm going on the premise that they sound similar.
I changed from Audience AU24 to Stealth Hybrid MLT's recently and the major differences I would comment on between those cables are:
1. The Stealth's are more detailed, I can make out vocal passages that I couldn't quite understand before. I can hear things going on that I wasn't able to make out before. Also, attack's are sharper and decays are longer.
2. The Stealth's are more transparent. What I mean by this, (I hate all these reviewer like terms :-) ), is that the instruments stand out on their own more, they're separated in space better and the "absence of sound" between them is more noticeable. I guess this is what people mean when they say that they have blacker backgrounds.
3. A friend who was over a couple of days ago who has good ears felt that they sounded fuller than the Audience cables.
4. Finally I find that they do a more realistic portrayal of the timbre of instruments than the Audience cables. Maybe this is why my friend felt they sounded fuller.
Basically, I bought the Stealth cables because when I first added the Hyperphono and then the Metacarbon to the system, I liked that they provided nice detail, did not sound bright and had a very relaxed and natural quality to them.
When my wife and I go to Symphony for example, I always notice how the violins are high pitched but there is no grating whatsoever and everything has a relaxed natural quality. These cables move my system towards that ideal. They help my system sound more like real music I suppose.
The AU24's are very nice cables but the Stealth are simply better, (which they should be for the cost difference). I hope this helps.