If you take the time to do the math,, and compare blade tip speeds,,
the Cub Cadet decks just turn "slow"
A nice cutting deck will be turning fast, and it is a significant difference.
My only success with a Cub Cadet deck was achieved by using a different deck pulley,, that sped up the deck blade tip speed.
My Gravely 24G runs crazy fast tip speeds compared to any IH GT,, and it shows.
That machine can make a sows ear look like a silk purse,, because of the tip speed,,,