said by houdinitrick :
If I decide to upgrade from DSL to fusion, would I need a new modem?
Depends on what modem you have currently and which Fusion service (single line or dual line bonded) you are getting.
If your existing modem supports ADSL2+ it will probably work for single line Fusion service. You will definitely need a new modem for bonded (dual line) Fusion service.
I don't know about the rest of your questions. Probably only Sonic can give you a definite answer for those.--
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