Firstly, I want to stress how grateful I am personally for all the work the transcribers carry out on this site. If it weren't for their efforts many of my ancestors would still be 'missing'.
Secondly, however, I would like to make family history researchers aware that I have found (and requested correction of) quite a few transcription errors.
So if you really can't find someone you know should appear on the site, do try and find other ways around the problem - bearing in mind that checking the name variants option doesn't always work. For example, I just couldn't locate the Armitages I was pretty sure would have appeared on the 1851 census, so I tried rearranging the name and found them all under Arimatige!