I inadvertently miswired the control module on the initial unit and it was purely my mistake.
I have no clue why the replacement quit working. I assumed by the way it failed it was something overheating on the control module as it would take time to become inoperative. Eventually it died completely but luckily for me it went out at a height that is not too low. It has the ability with a jumper on the junction board to revert to the stock system should it be needed.
In defense of the seller, I have found his customer service to be superb though the international shipping is inconvenient. When I get around to swapping the new module in and sending it in for repair I may learn what the failure was.
Worth is a relative term. I find the system to be a 'cool' mod, that is being able to raise and lower the car at will along with the visual feedback of the LED bargraph. It's worth to you will be based on your personal preferences and expectations with your car.