Middle name or double first name?

Liv

We have decided on a name for our little girl. I have always needed to have Grace as part my child's name to honour my grandmother, so we have decided on Mia Grace.

Now the tricky part.

We LOVE the way it sounds together, as one name. We know lots of people with "double first names" and I really love this option.

What does everyone think?

Have Mia-Grace as the first name or just Mia with Grace as the middle name?