I remember buying a similar bit from my local hardware store a few years ago which cost a little more and was only 5 pieces. 8 bit times have definitely changed and they are of a much better quality than those old beats. I use them mainly for drilling holes in the bottom of porcelain vases and sometimes for drilling holes in a tiled wall. For me personally it is much easier to drill holes in porcelain vases than in tiles. Maybe the tile is a little thicker, but either way they did the job much cleaner and faster than my old drill bits. For personal reasons, I usually start with a smaller exercise just to get started or as a guide before moving on to larger exercises. I think this works well, and of course it all depends on how powerful the drill itself is. Remember to drill with water and don't over drill or overheat these bits lest you break or damage them. Overall these bits are good quality, much more durable, sharper, tougher and stronger than my old ones.