I'm using Ubuntu Studio right now with the KXStudio repos enabled and a low-latency kernel. I'm very happy with this setup. I used to have an Alsa loopback device for Youtube, but the Alsa->Pulseaudio->Jack bridge through Cadence works flawlessly for me and so that makes everything easier at the moment.
If Jack is dying on you then you should try to debug that. It's supposed to be a software prepared for real-time performance. I actually don't think I've seen Jack crash on me with this setup, but I have a friend that has a low-budget notebook with insufficient electrical current available at the USB ports. A hungry audio interface would get intermittently disconnected and that in turn made Jack crash. But that's a hardware issue.
If you press many keys on your keyboard, do you see something unusual if you ask dmesg?