If I install 10 cameras in an office setting do I run the risk of my Wi-Fi network not being able to keep up with the data usage?
Should be fine if it is the recommended 802.11n type router. If it is an 802.11g or below, I might expect some issues.
Is the data constantly transferred somewhere or is it stored in the SD card until I want to review the video?
Data is pretty self-contained in the camera except for some handshaking protocols to keep connections open and confirm you are authorized to view the stream. When you watch the live stream, go into SD card playback mode, or an alert clip is generated, then there is network activity. I typically have 4 cams up on live stream all day on one device, so I generate a bit of traffic.