Depends on your line of work. As an electrician I use them daily.
For a pro, this makes sense. There are probably only a couple of sizes that get used regularly anyway (1/4" and 5/16" ?).![/B]

anybody have a recommendation for a us made long shank, magnetic metric set? i use nut drivers often and especially like them for hard to reach spots.
Try Xcelite or Klein (Vaco).

) Urrea (ever hear of that brand?) and yes even a couple of nut drivers from Facom. 
Don’t need them if you have a 1/4” drive handle and sockets. Useful tool
For the most part, yes. A socket set and spinner handle will work fine. But there are a few advantages to a dedicated nut driver.
Most nut drivers have a hollow shaft that lets you get down over a long stud that a deep socket may or may not clear.
They are also handy to have a set, such that you can use several at once without changing sockets.
It's also very handy to not run the risk of the socket popping off and falling down into an engine bay or down into some piece of machinery.
Color coded and ready to go makes them fast and easy to use.
For the most part, yes. A socket set and spinner handle will work fine. But there are a few advantages to a dedicated nut driver.
Most nut drivers have a hollow shaft that lets you get down over a long stud that a deep socket may or may not clear.
They are also handy to have a set, such that you can use several at once without changing sockets.
It's also very handy to not run the risk of the socket popping off and falling down into an engine bay or down into some piece of machinery.
Color coded and ready to go makes them fast and easy to use.
They are nice when you need to “feel” what your doing. You don’t get the same feedback with a ratchet.