"I always mean to have a spare in the "plumbing tools" box but always forget until one breaks. Using with 107mm core and holds centre excellently once I use my dead-blow hammer to fit in place. Cannot say the taper drills are easy to remove so why don't they just design an SDS special for the job?"
"I have made a big mistake and lost the pilot bit to my core bit set which renders it useless. But Screwfix to the rescue, so I now have two pilot bits and can do the job that should have been done 2 weeks ago."
"The core drill must be used with a guide drill. This fits the Screwfix core drill with the matching taper to locate the guide drill. I expected the guide drill to stick fast in the core drill, but it vibrated loose several times, drilling through the wall. Provided that the core drill is withdrawn from the wall as you switch off and the drill is still turning slowly, it shouldn't be a problem. The core drill came with very good instructions for its safe use."