lined ones should always stay the same length, and not stretch. With ordinary ones the side you always get up on stretches and just a little bit off is enough to put you off balance.
Lined ones are thicker so might create an uncomfortable bit under your thigh.
I just have regular ones and try to swap them over when I'm cleaning the saddle and I get up both sides anyway. They are fairly old now so I will probably replace them as the buckles have worn where they sit.. my legs are still the same length so I can't change that! Lol
Regular ones tend to be cheaper , lined ones might last longer.
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