The water tank of the S-9 and A10 are SO dramatically different, I really cannot understand what advantages were the engineers thinking of when they designed the A10 water tank. What were the design criteria for taking something that was so simple and replacing it with something so complex? Especially when the downside is that the A10 tank is almost impossible to clean because one cannot reach all the surfaces of the tank. I can't see any advantage to the new design. Hopefully someone can enlighten us--I'm eager to learn.
Sorry, but your description comparing the S9 water tank and the A10 water tank seems to me to be completely wrong.
You say that the S9 is "a lot more complex"? It has two simple parts, a top and a bottom--and both parts allow easy access to the whole part for gently wiping the surface with your hand while washing the tank.
The A10, on the other hand has three parts: a bottom tray, a plastic piece that surrounds the perimeter of the tray, and a top plastic piece. The top part is a remarkably complicated set of plastic surfaces and tubular sections which one cannot reach with your hands or fingers to clean the surface, and the bottom part of the tray has plastic and metal in layers with a little hole through which liquid and moisture can gather with no way to clean out--even with a Q-tip. So how can you say that the "A10 is pretty much one piece".?? Are you really a customer or are you a customer-rep? You can't be looking at the same thing I am when comparing the S9 and A10 water tanks.