If you're out of ammo, you can switch to this amazing energy weapon with adaptive frame. Actually, rapidly swapping to this weapon is highly recommended in many situations due to the Backup Plan trait, which grants reduced charge time and increases handling speed.
Apart from that you can count on higher damage from the rounds coming at the end of the magazine. Since this is an energy weapon, it has various ways of getting a lower recharge time and increased range. Many random perks have these effects so you should be able to have them almost every time.