I used this organisation to order my Grandfather's birth certificate. They are absolutely hopeless. They told me they could not trace it, despite me supplying them with the index vol and page #'s and his date of birth and district where the birth was registered. They then charged me £21.97 for their troubles.
I went to the General Registry Office with the same information and they supplied me with a birth certificate within a week for £7.
Do not use gov-certificates.co.uk They do not supply any contact phone numbers and their e-mail replies do not answer any queries and all in all their service is very unsatisfactory.