said by sk1939:Actually it would host a lot more than 667 DSL users. Transit is over-subscribed by pretty much all ISPs. I would guess 1 gig of transport would be enough for more like 5000 or more 1.5 megabit DSL customers.
That argument is completely pointless.
Transport for this area costs $4000 a month for a Gig of transport. That came gig can host 667 DSL users at 1.5 mbps. At 21.95 or so for DSL, that's $14,640 a month - $4000 for transport = a monthly profit of $10,000. Support, billing, and customer service for 600 users can be quite comfortably paid for by that, and these numbers assume no over-subscription which DSL and more so cable, are notorious for.