Editor recommended because this is the officially named Prestige Attachment for DS20 MIRAGE. It is not labeled BEST. Tradeoffs are quoted from official launch copy.

DS20 MIRAGE
UnderbarrelMirage Tandem LauncherReach maximum Weapon Level and Prestige the weapon.
Internal upgrade to the integrated launcher to fire two powerful explosive shells.
Attachments 1
- UnderbarrelMirage Tandem LauncherReach maximum Weapon Level and Prestige the weapon.
Internal upgrade to the integrated launcher to fire two powerful explosive shells.
Alternatives
- Base weapon / no prestige attachmentKeep the base gunsmith path if you do not want the official prestige tradeoff quoted above.
Evidence basis: Source
For streamers: add this as an OBS Browser Source — stream widget
Recommended · bo7-ds20-mirage-prestige-launch