I am getting AT&T installed next month. They have there own modem/router gateway. I currently use my own Motorola SB 4220 modem with my Time Capsule with Comcast. Can I have the gateway as the main wifi in the living room, the time capsule in the office for wireless backups/expanding wifi/run a wireless-n network, and have the airport express in the bedroom for expanding wifi/wireless music? I have a mac mini in the living for playing movies and it also holds my itunes library. our computers read the library wirelessly so right now its wireless-n.