A:Answer It can do legal and letter, but not at the same time - you tell it the paper size before starting the scan job, and if you tell it letter, legal scans will be cut off, and if you tell it legal, letter size sheets will be padded with whitespace. You can append different jobs together, though.
Scanning speed depends on choices (color, resolution, duplex, etc).
PDF is one of the output options, also various image formats.
This is based on scanning with Brother's iPrint thing on MacOS - other versions may be different.