You can apply the same line of thought to choosing a power saw, sander or any other power tool. Special features, like keyless or wrenchless chucks and collets are extremely convenient and well worth the additional cost, but only if you'll be using the tool a lot. If not, spare yourself the expense and get a simpler tool of comparable quality. Unless you're assembling esoteric electronic components, these things are a waste of time. The battery packs rarely have much torque and only three or four of the bits would get used in typical household applications.
Hand tools have their glamorous cousins, too.
If you're an electrician performing a task repeatedly, these things are great. Otherwise, standard tools of high quality are your best bet. Finally, there's no substitute for experience. If you know someone who's a contractor, hobbyist or even a clerk at a hardware store, ask his or her advice. These people are generally eager to share knowledge about what to use and what to steer clear of.