Both of these 2 Shark Rocket series are Ultra-light Upright vacuum cleaners.
The Shark Rocket Complete with DuoClean HV380 Series includes several models such as the HV380, HV380W, HV381, HV381C, and HV382.
The Shark Rocket DeluxePro HV320 Series also includes several models such as the HV320, HV320W, HV321, HV321C, HV322, and HV324Q.
The main difference between the HV380 and HV320 series is the floor nozzle design.
The HV380 Series features dual brushrolls, a soft velvet brushroll and a bristle brush, to clean small, large, and stuck-on particles from hard floors and carpets, they call it DuoClean Technology.
While the HV320 series models only has a bristle brushroll. However, the HV320 models can use the HARD FLOOR ATTACHMENT that will not work with the HV380 models to clean hard floor surfaces.
With the HV380 models they do not require this as they have the soft roller on the floor nozzle for cleaning bare floors.
Maintaining the Brushroll.
It is easier to remove anything that wrap around the brushroll on the HV380. You just press or slide buttons to remove the rollers from the HV380, whereas the HV320 requires you to use a coin or other tools to unlock the three locks on the bottom of the floor nozzle to access the brushroll to check for or remove any blockage.
HV320: 120V, 60Hz, 500W, 4.2 A
HV380: 120V, 60Hz, 600W, 5.0 A
The HV380 is heavier than the HV320.
They have many similarities.
Two Speed Brushroll.
2X dust cup capacity versus HV300.
Can convert into a Hand Vacuum.
LED lights on the hand vacuum and nozzle to spot hidden debris.
On Unit Storage Hook.
Onboard Accessory Storage.
Fingertip controls for carpet and bare floor cleaning.
Can be mounted on wall.
You can read manuals to learn more difference between Shark Rocket Complete series HV380 vacuums and Shark Rocket DeluxePro Series HV320 vacuums.
Shark HV320 Manual – http://www.sharkclean.com/include/pdf/manual-HV320.pdf
Shark HV380 Manual – http://www.sharkclean.com/include/pdf/manual-HV380.pdf