I have an Epson 640U, and apart from SANE not knowing about its 1200dpi
scanning mode, it has worked flawlessly for me.

(...that was, after I back-ported the -current USB driver to 1.5.2 so that
I could use it: see http://hunter.apana.org.au/~cjb/Code/usb-scanner.diff
The 640U is known by 1.6, if applying kernel patches from dropout uni
students isn't your thing..)

-- 
Chris Baird,, <abuse@brushtail.apana.org.au>