I prefer how the nylon sheath rides on my belt. But the nylon seems to get dirty, but cleans well. It was riding a little too low, so I put a safety pin about a half inch from the top of the loop. I have had the original wave on my belt for the last 4 years and the sheath is still going strong. Same safety pin for those 4 years as well.

Ready

Nylon - no contest.

My Leatherman PST (or is it a PST II ??? what's the difference ? is there a different marking on the tool ?) came with a nylon sheath.
I have worn it for some years now.
Still good.

As for leather, I ordered a combo sheath (PST + SF6P) two years ago from a canadian guy. Paid for it. Never got it. Too bad...
So I can't tell ...

But I would say it sure looks better ...

I have the Charge Ti which i think is great, but the sheath it came with was awful (it was the leather one). then i saw the nylon version made for the Charge and it's just as bad! i've been using the nylon sheath from my original wave for over a year now with the Charge. i had to replace the loop side of the velcro once but other than that it's great.

The main reason I like the nylon is that it has sideways carry loops. I feel it does not snag on things as much (or poke into my fat gut as much <img src="/images/graemlins/laugh.gif" alt="" /> )

Technically, my leather sheath for my New Wave has sideways slots, but the belt has to be fairly thin (both in width and thickness) to go into the slots that way. And good luck pushing through a webbing type belt...