I had 2 of these lamps for years. As a bedside lamp or otherwise I had for years only occasionally and relatively short (can occasionally have been a couple of hours) operated. I do not know more precisely whether the cracks were already readily available when I used them on the desk, but after I've used as a desk lamp and daily 8h had in operation, fast large cracks in the housing have occurred (by including the telescopic rod and through the switch). As now even all 4 slots for the bolts are broken, although I have not actually changed the setting, I have now bought other lamps. The problem seems to be the rather large amounts of heat through lack of ventilation. The quite similar lamps of mouth have holes and are much cooler after 8h.
Still 3 points since they are reasonably priced and have kept at intermittent duty, long.