I'm not sure if your plumber friend has a number that means anything...
He might be talking about the Toto Carusoe MSRP $201.00 http://www.totousa.com/productpage.asp?PID=662
This Toilet does not have the G-Max Flush that the Drake has!
Don't get me wrong here the toilet is still a great toilet that has the same Toto quality but yes it has the same smaller flush valve that is found in many of the less expensive "builder grade" toilets out there.
The Toto Carusoe MaP Tests has it flushing in the 600 Grams of Solids Per Flush which puts it about 2-3 times better than the comparable Kohler Wellworth & Am. Std. Cadet Vs. The Toto Drake which has the G-Max Flush which MaP Tests at 900 GmPF.