Wonderful news for those interested in medieval Cornwall!
DCRS have just this year published a new volume which I have just seen for myself: "Cornish Wills 1342-1540". Edited by Nicholas Orme, Emeritus Professor of History at Exeter University, it is an anthology of wills inside Cornwall as well as those outside that have Cornish references for the period in question. Most of the former are also full transcriptions, and these are in unabbreviated, modern English. There are also brief biographies of each of the testators, a glossary of terms, and two indexes. Some 122 wills are covered, with extracts from 66 more.