1) Kydex is what, a 7 or 8 on the Rockwell scale? Compared to 59-60 for the SR-77 ? I don't think you need to worry about it. Evenso, if a sheath is made properly, the edge never contacts it anyway. (and no, not all of them are made properly, but Rainwalker's look just fine in that regard)

2) Again, a properly designed sheath can be extremely quiet.

3) Kydex is thermally stable to well below zero, especially if worn on the body.

4) Sheeple's eyes will go wide, no matter what, so why bother about that? Do you think their thought process goes like this: Hey, that guy is wearing a knife! <img src="/ubbthreads/images/graemlins/eek.gif" alt="" /> Oh, wait, he's got it in a leather sheath, so he's ok....."

It is more a matter of location on the body and your attitude than sheath material.

Leather is hard to clean, especially on the inside. For example, I make my kydex sheaths so they can be cleaned the entire length of the interior. I've never seen a leather sheath that allows the same thing.

When leather gets wet, your sheath integrity suffers. The sheath may even be permanently compromised as a safe way to carry the knife.

It retains the water, making rust on your knife a very real concern.

In jungle environments, leather and nylon do not hold up nearly as well as kydex.

Speaking of safe carry, if you fell head first down an incline, the knife could go right thru the leather. The term "jump safe" comes to mind.

Kydex scoffs at water and it's "jump safe" (again, proper design required)

Leather has many good points. Kydex does, also. Overall, I prefer the performance of a properly designed and executed kydex sheath.

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