I mean they could use a Fiat 500, or some other modern car...but what would the fun be in that?
We've got one in the local car museum, it gets driven out and about every 18 months or so.
Crackin' fuel efficiency: https://en.wikipedia.org/wiki/Isetta
In every case I'd rather be in the Fiat 500. The only benefit might be the Model T attracting more attention, but some flashing lights and a garish "Road Maintenance" paint scheme could solve that for the Fiat.