So, you know a brad point drill is right for your purpose, but you still don't know what to consider when buying. Don't worry, as there are relatively few things to remember, and they're all fairly intuitive and should come naturally as you go through the trial-and-error-based shopping process.
Steel-Brad tip drills are available in a variety of woodworking materials. From softest to hardest, prices go up, they are carbon steel, high-speed steel, titanium coating, and carbide. Now that you can easily use HSS on the hardest hardwoods, they should be your first choice. For long-term jobs that require drilling a large number of holes, carbide tips will last longer but are hard to find. For softer woods, you can even use carbon steel. Although we don't recommend using them for hardwoods.
Size - As we mentioned earlier, brad tip drills are smaller in diameter than spade drills and Forstner drills, usually measuring between 3/32 and 1-1/4 inches. 1/16 inch is too small to be pointed. However, planning your build carefully means you don't have to buy a full set or have everything on hand, and for most simple builds, such as small shelves, you probably won't need more than two different sizes. You may need to buy individual drills before you commit to a specific manufacturer and buy a full set.
Brand - A bad drill will ruin the finish and firmness of the workpiece. However, a bad drill can give you many signs of poor performance long before you reach the finished workpiece. If your drills keep wobbling, or they're not properly clamped, that's always a bad sign. If you break one by one, or if you're drilling an unbalanced hole, chances are your bit isn't real, so it's vulnerable to chipping. If you find that your drill is getting too hot, your material is running too fast, or you have a poor-quality drill on hand. The point is that you need to be able to tell what's a good buy and what's not, which usually doesn't become apparent immediately after your first job. The wear rate or dullness rate is an important part of helping you make a buying decision.