No - they are all in the same weight range maybe 40-60Lbs +- for all the commercial machines with the same deck and engine size. Obviously a 72" Diesel water cooled machine will be much heavier than a 48" 19HP unit by probably 300Lbs but thats apples and oranges.
The Ferris does weigh a bit more on average, partially due to the suspension but it is not a huge amount, and IMO it rides so much better than non suspension models.