I've been looking at an LED-Wiz alternative too.
Okay each pcb has 4 x eight darlington array IC's. Which gives you a total of 32 outputs. The only way to increase the amount of output's would be to add more IC's, giving possible 40, 48, 56, 64, 72, 80... outputs.
As for the talk about "stutter". Well I've read through this thread, rather briefly though, and I couldn't quite grasp what was meant by this. I can always assume but that's not certain.
I take it it's more or less a lag issue related to the LED-Wiz?
The 5th chip, the one in the middle of the pcb is the USB microcontroller IC, rated at 1.5mbps and having internal RAM of 256 bytes. As I'm not certain on the whole stutter thing I'm not 100% though I do believe this could relate to the stutter issue....