You could install it in a VM like I did and then use bridged networking so it gets it's own MAC address from the adapter. From there you could set up priority based on that MAC or that IP address.
It's a lot but it works well. Otherwise, just try to limit how much bandwidth your other computers use. If you torrent at all, you will definitely need QOS turned on on your router.
If you only use your dongle on one computer, you could try creating a Virtual Server on your Router with port 5070 pointing toward the computer you use the MJ on.
I dont think it has much to do with bandwidth because it doesnt require much as compared to most people's broadband, i believe it has to do more with usb and how well your pc is running. Case in point, Im running a thin client dedicated to the dongle and my connection is faster than most, probably twice as fast but it still gets a bit choppy.
Sure... I was wondering if we MJ as a service gives better performance, as it doesn't have to do pop-ups or front-end windows..etc..
I have a feeling that after port forward for 5060 and 5070.. it has got little better.. but, it is still too soon to make such a statement.. I will watch it more and write back here..