Uh, you don't have to worry about which distro has support for any particular device. It's the kernel that would support or not support the internal device. If one distro can handle it, any distro can handle it. All it should need is a kernel upgrade or patch. And external is the way to go. If you buy your own modem the monthly charges should be no different for either as the DSL provider wouldn't know the difference. They may "rent" the external modem at a higher price than the Internal. And it would make sense that an external is a little higher in price, after all it does have built in ethernet, and a case that the internal modem would not have. Do buy the external modem and lower the monthly charges.