The second expanded edition is an exceptional collection of Arthurian materials from most of the major traditions - Latin, Welsh, French, and English. It runs from around 600 to the late 1400s, with both excerpts and full texts. The only missing tradition is German, perhaps because it relies so much on earlier French sources. Still, for the non-academic interested in Medieval Arthuriana, this is the text to get.
Excellent selection of readings. Of course, there is much room to quibble with the selection, but honestly, the editors had to make choices, and mine would not have been better, just different. I liked it, and I appreciated the various translations.