In the overall cost of the periscope, I'd be surprised if the original $30K controller was even 1% of the total. It's still $30,000 saved, but in the scheme of things this sort of economizing is not going to have any impact.

What's more important is they found a more familiar, intuitive, hence better controller device. That it was also much cheaper was just a little bonus. If the savings in training hours are to be believed, that will be a much greater savings than the cost of the hardware.