The 121 actual weight is more like 4.5 tons. A 1 ton difference isn’t insignificant when it’s over 20 percent of the total weight. Also the 121 was rated at 42 hp where the e35 is rated at 25 hp to avoid emissions. The e35 was also available at 33hp but I’m guessing most buyers get the 25 hp one. The 35 series kubota is also 25 hp where the 40 series gets a pretty big boost to 40 hp. I’ve never ran a 3.5 ton class machine but I’m guessing you would experience a pretty big difference in the hydraulic speed with such a big difference in engine power. One of my friends used to own a 3.5 ton bobcat although it was probably a early 2000s model, I don’t know exactly. I never ran it but he has used my KX-040 and says the 40 is drastically stronger.
