Relying on DURABrite ET Ink, the A3 printer promises to deliver print quality that wont be a letdown.
As for double-sided documents, the speed is up to 16 ipm for A3-size documents printed in black ink.
Scan speed partly depends on whether you use the flatbed or automatic document feeder.

If it is the former, the speed is up to six seconds at 200 dpi.
Scanning single-sided documents with the automatic document feeder is faster than scanning the double-sided ones.
26 ipm is the highest achievable speed for black pages at 200 dpi.

Color pages take longer to finish with a speed of up to 9 ipm.
Fax resolution is 200 x 200 dpi, and data transfer rate is approximately three seconds per page.
But there is no mention as to how long the time it takes to fax double-sided pages.

In the case of Epson L15150, the ink supply is handled by four ink bottles.