I'd only use it if I lived in
Ireland, or if my Irish heritage was so important that it'd make the constant corrections of spelling and pronunciation worth it. For me, it wouldn't be worth it (as a person who constantly spells out her name). For a mn, I'd avoid a 2 syllable name.
Deirdre AureliaDeirdre AzuraDeirdre BelleDeirdre CorinneDeirdre EleanorDeirdre IsabelDeirdre MercyDeirdre Scarlett