I just bought 2 other power packs, otherwise identical to the DP-20DMXL's. I won't mention brands, but it was half the cost, and had those new features in it as well.
Too bad it's not just as simple as a firmware update. Regardless, way to go, ADJ! Having that feature in there brings much needed flexibility to that product line. Really, you can kill off the PP-20DMXL model since the DP-unit can do both fuctions. That feature makes it easier to configure trusses of lights.