Lectric has just come out with a cargo bicycle, the Xpedition and it has many upgrades compared to the RW4.

From what I've seen, it is lighter, more powerful, comes with hydraulic disk brakes, has 20x3" tires, and is available as a one or two battery model for hundreds less than a RW4. Also, the rear rack accessories seem better thought out than Rads.

Seems that Rad is going to need to make an updated Radwagon to be able to compete.