I used to use plastic rim strips from a major tire manufacturer (can't remember who), and they worked fine for a while but always wound up getting brittle and cracking where they are pressed into the spoke recesses. This may have been because my bikes live in an unheated garage and go through many freeze-thaw cycles, but Velox Fond de Jante (otherwise known as Fond de Jante model X073A) are long-term reliable.