Excellent drills!!! I have all sizes up to #13 and satisfied is an understatement!!! They excel in drilling ability compared to regular iron, due to the cobalt alloy. In smaller sizes as well, they show exceptional resistance to breaking if pressure is applied incorrectly by the user. The regular iron ones simply break like toothpicks.
Also, I cannot fail to mention that they have a super price for what they offer!!!
They are highly recommended for professionals and non-professionals alike. Perhaps the most value-for-money solution for drilling.