The MT design makes using these sliders as a step difficult espescially for children as the gap between the slider and body is somewhat wide. I like Slee's design better based on this feature. But for folks w/o the small kiddos, the MT design is awesome.
Interesting observation. I would have figured that the MT's would be better for kids as the gap between the rail and bar is pretty tight compared to BIOR/WKOR. Agreed, that the Slee Step Slider is the best for ergonomics.

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