I don't think I'll need front weights on my 2182 with the 60" Haban deck under it, a smaller machine with no deck would probably need them. The sprayer will be around 300lbs fully loaded but I don't see me ever filling it over 20 gallons for my yard.
I fully understand the safety aspect of spraying, I have my pesticide applicators license and cover 6,000+ acres a year with this machine.