Just a note of caution.
An increasing number of local councils, who employ the staff who act as registrars for GROS in Edinburgh, are offering local research possibilities.
These range from the Park Circus model offered by Glasgow District council and others which are a 'mini' New Register House, i.e. you have your own search terminal, sometimes linking into the GROS/NRH DIGROS search system; through to other locations where the local registrar offers an assisted search, i.e. a staff member, working with you, carries out the searchs that you want.
At Park Circus the cost is £14/day. Elsewhere, for assisted searches, the cost can be up to £30/hour. In the latter case, especially if there are a number of lines to research so that the time required could be well over an hour, it makes sense, even if extra travel and accommodation expenses are involved, to give serious consideration to visiting the main research facility in Edinburgh, where the cost of a daily 'ticket' is now a paltry £10.

As regards the Park Circus facility in Glasgow, you need to book at least several weeks in advance as it is very popular; and advance booking is often also essential elsewhere.
Wullie