I have 2 sets of Craftsman carbide lathe tools --they are my best but they do need to be sharpened on occasion--not as much as HSS or Carbon tools .
You can get an edge on them to shave with if ya wanta -Craftsman made most of theres in late 50 -60s is what I'm told--
Have seen Bens-Best advertised but havent tried theirs yet -I wouldn't trade mine their that good --watch the e---- occasionall some one sells a set - Happy Turning