While, the concept of mirror will is more known in the Western countries, the relevance of such a will is not known in Indian sub-continent.
Points to note in case of Mirror wills
Mirror wills of the couple are exact replica of each other with respect to executor of the will and bequests (a gift of personal property by will). In the mirror wills, spouses appoint each other as executors of the terms of will. An extra executor can be appointed as a safety step to ensure that the duty of executor of the will be performed in case the couple meets death simultaneously.
In case the couple has minor children guardian shall also be appointed in the mirror will for looking after them.
An important aspect in the mirror will is however the common interest of both the testators of the mirror will (spouses in relation) to bequeath financial asset after death to the spouse.
Disadvantage of Mirror wills
Mirror wills hold relevance only in a case when all the property held by the couple is jointly owned. So, in a case when some portion of financial assets are under the ownership of a single spouse, it is at best to get separate wills drafted.
Further, in case of disposal or purchase of some asset, the couple needs to work in tandem in respect of the mirror wills as changes in the wills are not effected automatically.