I never had a problem with the dual action agitators...the first one I installed on a whirlpool, never shreded anything and seemed to work better with a full almost packed load, as in their demonstration, but it did work alot better in the belt drive rather than the direct drive, the DD was moving so fast and short strokes that the corkscrew never seemed to move anything, and then in the newer models they angled the vanes downward which helped a lot, but in gentle speed, with hese agitators nothing moved, so I really preferred the larger KA agitator for a DD application....
but I did find the 1-18 frigidaire to be boring, like what was said earlier, unless its a tiny load with a lot of water, that thing would bob up and down, and the load would just sit still....