The difference between the Progressive 412's and the 440's is the 440's have better valving.
The difference from stock to 412's is markedly better across the board and the difference between the 440's and 412's is just as notable as reported from those who have made those specific transitions.
In selecting the shocks if you exceed the manufactures gross weight (rider, gear and passenger) of 440 - 50% of the time then you need to go to the Heavy Duty Spring in the 412. NTKS (Nice To Know Stuff)
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