Four wall boxes each with two Hubbell duplex receptacles? Use 6-inch pigtails in each box. Each wire nut -- one for black one for white -- will have 4 wires. It's easier IMO to use pigtails in ganged boxes. Also, pigtails are a better job -- reduces voltage drop and heat build up and removing an outlet keeps power flowing. As far as grounding, if you are using metal boxes, I would suggest pigtailing the green wires to the outlets and to a set screw in the box instead of relying on the receptacle ears to make the contact ground. This pigtail will need 5 wires -- two from each feeder, two to the receptacles and one to the box.
As always, check you local codes. A licensed electrician is your best insurance policy.
As always, check you local codes. A licensed electrician is your best insurance policy.