In my experience, a scan to email in colour 300dpi is scanned and sent in approx. 10s.

According to official data, the scanning speed via the document feeder is 26 pages per minute single-sided and 35 pages (17.5 sheets) per minute for double-sided scans.
In addition, the data transfer is the fastest, whereby the connection via the network (Gigabit Ethernet connection) or via the USB 2.0 connection are the fastest.