Hi, I have found the 1939 register very helpful - it has helped me identfy other family members through using the information on the 1939 register.
For example, a marriage between my gt uncle and his wife provided a vital clue as to who my gt Aunt had married as she was a witness at two of her brothers weddings. (I got his wife's name from the register and then searched for the marriage record and ordered the cert)
Another household helped me verify that I was looking at the right family - address in register matched death certificate address.
It also helped with identifying the actual DOB for some relatives and also helped me grow my tree because their children were showing on the register. I now have names of 'Holland' Relations that are still alive today through tracking of birth's with the surname Holland and the said mother's maiden name - although to track them I would have to use Facebook or such like as there are alive!
Although some actually come up on the electoral roll register results, from which I traced a gt aunt that is still alive today!!
I would definetly recommend it, just be sure you have some sort of clue that your unlocking the right household as it will get expensive if not!!
Happy Delving!
