We added similar unit to Dad's Dixie Chopper and I feel it helped. (birthday gift, for Dad)

 Dad at 88, He didn't seem to feel any difference.

That Mower is a solid square welded frame, only rear tire air pressure for any "flex".

Giving it some travel, at the front wheels, has to help.

{Note: don't want an air seat, because it raises seat another 3". I know Dad wouldn't like that increased height difference}