Lynxmotion’s Mini-AB board is designed specifically for the atom processors, but you can also use any basic stamp or the basic X processor as well, so the Mini-AB is very flexible.
If you plan to build any of the Lynxmotion bot kits, The Mini-AB has a bolt hole pattern to fit on these bots. The other board you mentioned may not fit without a custom fabricated mounting bracket of some sort.
The universal Development board is much larger than what would fit on the Lynxmotion biped.