I own a Weston Master 5 (newer than yours I know) and have found it to be an exceptionally reliable bit of kit. I purchased mine secondhand from the original owner and although it has never been checked or repaired it still works as well as the day it rolled off the production line.

I know that compared to some of todays modern meters at 300 a pop my little WM is kinda basic but I wouldn't change it for the world.