I've got both a Basic #3 and #9 with the Kydex sheaths. I like the Kydex since I canoe a great deal and its a given that whatever I'm wearing is getting wet. Plus, they don't require much to keep them in good shape, as compared to leather.
It's a personal preference thing - think about how you will normally use the knife and pick the material based on that.
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Knowledge without understanding is knowledge wasted.
Understanding without knowledge is a rare gift - but not an impossibility.
For the impossible is always possible through faith. - Bathroom graffiti, gas station, Grey, TN, Dec, 1988
AKTI Member #A000831