If you are making a will for yourself or just one person simply select 'Single Will'.
Please note that a "Mirror Will" is not just one document but two Single Wills that mirror each other with identical wishes.
For example, if two people wish to leave everything to each other it is easier and less expensive for you to make Mirror Wills.
You can make Mirror Wills if you both wish to leave your estate to the same people such as children or nephews and nieces.
If both of you wish to leave your estate in slightly different ways, the best option is to create two Single Wills.