Unless none of your family moved in the last almost 200 years, it's not your local office that you need to worry about.
Use of local Registration Offices has always involved the extra step of finding roughly where the family event occurred. Then you apply, usually by post, to the Office that most likely registered the event. If you send all the details that you know, including whether this is certain or just highly probable they can then use that to find the record or at least establish that they don't have it.
They usually have a phone number for a real person who can answer questions on what the details on the cert mean or sometimes even confirm in advance if you expect a particular father or a mother's maiden name, for instance. As an example, I have even been able to query whether a time of birth indicated a twin, and in that case no, all the entries on the pages around that date had times entered and no evidence for another child in my family at the same time.
This method also has the huge advantage that what you get in return is the "primary" evidence of the event registration, rather than a copy that was sent on to GRO (hence their certs are only "secondary" evidence).
Obviously, it does not guarantee that the details recorded are correct but, especially with the photocopy entries, it does ensure that you get what was recorded in the first place and not what someone else thought it said.
And with a Thursday to Saturday turn-around as I experienced this week, this system seems more efficient and much more suited to historical searches.
Sadly, as someone has pointed out earlier, not all local Registration Offices offer this facility but, where they do, then it would be my preference every time.
