This is ok ish for certain jobs the grub screws can come loose take note there are two of them and you need to make sure one is tight on to the flat part of the shaft of the drill bit and then the other one tightened up. for some jobs though the drill bit sticks too far through the countersink part so you will need a shorter drill bit but whether you would be able to tighten the grub screws on to a standard round shaft of an ordinary drill bit ,I don't know.
I have several countersinks and needed a new 10 mm so decided to try these, they are brilliant,
makes a neat and tidy hole for the screw head. Very impressed.