I used to have the oem plastic one, it eventually broke away and became useless. I changed the front bumper to the new Nismo one and needed something rigid for perfect fitment.
Can't speak for Zspeed but the Torqen one fits perfectly. Rigid aluminium, has been finished so it's not razor sharp and comes with the required hardware. Wish I'd bought one sooner!
It was more exciting on track though, wondering if a stone would pierce my oil filter