There aren't really alternate connectors. That said, I strongly zip-tying all extension cable connections and/or wrapping in electrical tape. Use the really thin zip ties, and thread them in between the wires on both sides, and you will have a connector that does not fall apart. Also, see the PWM cables at AndyMark if you want other lengths (
http://www.andymark.com/product-p/am-0695.htm)