I agree with your estimations about williams they are solid and run forever I have had no real problems our of my williams steamers any time i have used them on the Christmas layout. this also includes running them for up to 12 hours at a time with no break
Being as this will be in a work enviroment I would make sure that the Track and engine noise is as low as possible
with this being said i have always had good luck with a 1/2 inch OSB base with Dollar store carpeting glued to the base and then Un-soaked cork roadbed under the track and I also used Atlas Three rail track which was also screwed into place with track screws all the way into the plywood.
IN all the years i have done displays in public places the Christmas music that was played through a computer to speakers mounted on the layout always had no competitiion with the running of the Trains
the Cork Roadbed can be found at Train-land for 35.00 per case of 25 pieces
I hope this helps
Manufacture: MIDWEST PRODUCTS
Category: Tracks & Accessories