Gameplay:

Plenty of variety, and at least half of the titles are "classics" in the traditional sense.

Graphics:

The only graphical improvement option is screen resizing, which isn't that impressive. 

Sound and music:

Unlike other compilations, there's no added soundtrack - what's in the games is what you get.

Controls and Interface:

Mapping controls to consoles from the arcade can be a pain, but Midway did a good job with this set.

Overall:

Definitely worthwhile if you see one or two titles you want to keep. Peruse the available offerings before buying, and beware, some of them aren't nearly as good as you remember.