Satelite needs direct feeds to every location. From what you say theres a location where 5 Coax cables jump off a splitter to the 5 locations in the house. It sounds like this location is 'inside' your house. Your getting 2 receivers. I'm going to assume that you only have ONE coax to each location so the installer will run into 1 issue, which I'll get to later. He'll need to install a DPP LNB/dish w/ a DPP44 switch and bring 2 feeds into your house to the area where your splitter currently resides, where he will connect directly to the cable that feeds the 1st floor and 3rd floor locations. I think the vip is a dual tuner, but I could be wrong, the 625 defitntly is, the installer can use a seperator to feed ports 1 and 2 at the receiver. The only issue is how to get the '2nd room' output from the 3rd floor receiver to the 2nd floor TV. But you said you'd worry about that later. As far as internet, no they cannot share the same feed but as I said the installer is gonna need to bring in at least another feed for Satv so you'll need 3 total Coax's going into your house, 1 for internet, 2 for satv. You say you have Cat5 in your house, if its not allready being used for phone, you could use it for internet if it all feeds to 1 central location......place your cable modem there and distribute it to the whole house w/ a hub.