Cooking For Engineers has a very good post discussing kitchen scales. I find there are a couple of benefits to using a scale to measure ingredients. Measuring flour by weight is much easier than by using a measuring cup, you don't have to worry about consistent packing. Same is true with something like brown sugar. Ingredients like shortening are also easier to weigh than use water displacement or even trying to use a dry measure cup. Ease of measuring leads to repeatability, which is nice when I make the same recipe for sugar cookies or frosting I can become more consistent. The more variables you can control, the better you can do when it comes to baking.
I wish I would have found this post before I purchased my scale. Don't get me wrong, I like my scale and it works fine. But this post is very informative and explains everything you should take into account when you are looking for a scale.
The scale I own is the Salter6055. It has all of the options that Cooking For Engineers recommends and is in the similar price range.