I drilled around 80 5/8 holes with an annular bit, into 5\" steel i beams (10lb/ft). The water-cooling system worked really well. It took very little pressure to drill each hole. It was fast and made a job that seemed daunting very easy! The electric magnet worked really well too; it supported the drill sideways. Only issue is once you put the chuck and a full size bit into the drill, it hangs low. So you have to rig a setup where the drill is on the edge of something and the thing you are drilling is lower.