A couple of years ago I bought a pair of old battlewagon DW5000's, one single chain and the other nylon strap. The strap was worn to the point of being frayed, so I went in search for a superior replacement.
I did an in-depth study and comparison of different nylon webbings for use as bass pedal straps, and I came to the conclusion that the best qualities the webbing should have are flexibility along the length, but then stiffness from side to side. This makes for the most efficient force transfer without the pedal feeling soft or loose.
The stock nylon strap has plenty of flexibility, but it has it in both directions. This is probably just fine for a DW9000, with the big aluminum plate and ball bearing hinge, but for an older style pedal, say with a radius rod (like the DW5000's I had), it's kind of wiggly.
The best nylon webbing I found came from dog collars I got at the dollar store. I could have bought a roll of it from my webbing supplier, but I got 2 straps from one collar.
The Gibraltar kevlar one is great, stiff as hell from side to side, but it's about a 16th of an inch too wide to fit the DW cam. I trimmed it with a utility knife and it works great.
DW's stock strap is not "flimsy," as in easy to break or wear out, but it is pretty floppy.
They're cheap, and I had fun trying different ones out.
At the moment, though, my favorite pedal is an older small footboard DW5000 with a round "turbo" sprocket and single chain. I may go back to the strap drive, as I like how quiet it is.
Yes, I am very fiddly about my bass pedal. Endlessly tweaking it.