Regular readers of this group might remember I had a problem with this unit
a while back, I ended up buying a replacement sensor "insert" from German
Star in Arizona. Unfortunately the first one didn't work, neither did the
second replacement unit, so I gave up and went and bought the original Bosch
sensor, ouch! Anyway, the Bosch work's fine and the engine check light has
gone back to sleep again.
So, you pays your money and takes your chances with the "insert".