If you only have a 1" water line to the building, you will need a tank type toilet.
The plumbers are right, the meter and the water service need to be sized bigger for a Sloan Flushometer.
Any of the tank type toilets should work fine, as it holds the water in the tank, and then drops it.
If you are going with standard height elongated, then the Drake and the Ultramax can be gotten with Sanagloss
If you need the higher bowl and Sanagloss, then the Ultramax II and the Drake II.