We have a job which required 800 number 22dia holes drilled 200mm into unreinforced concrete we purchased 5 drills from yourselves for this task the first drill did 31 holes and broke, the second drill did 36 holes and broke, your drills are slow drilling and do not clear the dust from the hole efficiently. My team have resorted to using two older hilti drills which have now drilled in excess of 500 holes on this job and are still going strong. So my review of your product is that I am disapointed. Whilst I appreciate that your drills are significantly cheaper, Hilti although expensive do appear to be a better option in the long term and in speed of production. Bob Grant