I've drilled with both the 18x450mm and with 6 and 8mm some holes and I have to say the drills are useful, but certainly not professional quality, what I have to the price certainly not expected, after one year now catch the first even unused drills to rust on something but surely the function does not restrict. For the occasion drill (lamps hang every now and then a cable through the wall drawing, etc.) recommended in my opinion, for everyday use at a construction site I would, however, spend much more money.