"There is a bit of a problem if the depth of the hole you want to cut exceeds the length of the screw in the centre.
The bit features what is effectively a removable screw in the centre that helps it "self feed". This caused no end of problems because it would drill itself in and get stuck - it trashed my 3 year old drill! If you remove the screw the bit will not run true in the hole. Trial and error (remove and replace the screw constantly) and you'll get through.