A beginning box maker asked "which is better for box making, a compound miter saw, or a table saw?" And the answer as in most cases is, "it depends". You can buy a very good compound miter saw for much less than what you would spend for a reasonably good table saw. So if you are comparing what you can get for the money in terms of accuracy and quality of cut you may get one answer. Ask a few other questions and you will come up with another view.
First of all you need to understand the tools. A compound miter saw was invented as a carpenter's tool, portable, to be taken and used at various job sites for installing moldings and trim detail. The good ones are very precise.
A table saw, on the other hand is designed as a more general tool, adaptable to a variety of wood shop functions. It will rip lumber to width, and cross cut lumber or small parts to length, and do lots of other things besides. But in order to do all those things with some degree of accuracy, you will spend a great deal more money on it. You lose the easy portability, as the good ones are heavy.
The real problem with compound miter saws in box making is when box parts get small. It is difficult to hold or clamp small parts in place on a compound miter saw. Clamps get in the way of the motion of the saw unless the parts are long enough that they can be clamped some distance from the blade. When using the table saw to cut parts of similar size, you can use a sled, and stop blocks and simple hold down stick to control the stock through the cut, so in my experience, the use of a table saw is preferred. And yet, there is the problem of cost. If you plan to do quality work, cheap table saws should be avoided. You would be better off buying a used, quality made machine rather than those on the market that are little better than an upside down Skil saw in a stand.
Buying tools is not the best way to learn their use. It can be good to take a class and get experience on real tools. I have three box making classes coming up this summer. The first is at William Ng's School of Fine Woodworking in California, June 8-12. Check it out. I would love to see you there. The photo above is from my class at William Ng's school, June 2007.