The main difference is that the EL Escudo Dos is an Arduino shield. It's meant to stack on top of an Arduino, which is the controller brain of the setup. The EL Sequencer has an Arduino-compatible microcontroller on the board, so it does not need an external microcontroller.
We have tested them with SparkFun's 3V and 12V inverters, but we have not tried something of that power. We make no guarantees it will work. However, we would love to hear if it does!
