FWIW, I just had a realtek USB ethernet adapter take down my network twice last week when I was trying out with an Android tablet.

It's part of a powered USB hub, and it works fine while the tablet is connected, but after disconnecting the tablet, the ethernet controller stays active, and about half an hour later my entire home network stops working. I had to disconnect the realtek adapter and reboot my network switch each time.

So, their problems are not entirely limited to mac.