Replacing the timing belt is preventative maintenance, and I highly recommend having that work done when Acura recommends it. Their cars run very close to specification, and if you do not replace the belt, you run an increasing risk of the belt breaking, which has the potential to do very expensive damage to your engine.
If in the event that your belt breaks, you will need to rebuild your head and replace valves. The should replace the water pump at the same time and adjust the valves. Probably cost $600-800. At the dealer. I would replace it. The belt is rubber and the material breaks down after time. Hence the mileage or how old vehicle is.