I ordered a rubber Cinturini strap off Amazon to replace my Bathys strap that broke. In the process I felt like there was enough fumbling and frustration in cutting and adjusting it that others may have the same trouble.
This video is crazy detailed and you will cry with boredom if you are adept with strap changing, etc.
The main advantage of the video is seeing this strap up close so you know what you're getting into if you order one (I didn't).
The strap has been great - I'm happy with the purchase. I'd definitely buy another one. The one in the video is a 22mm. Last I searched Amazon they were out, but had the 20mm.