Minecraft Mods: difference between NEI and TMI?

So I realize that Too many items will not show any recipes, but why does not everyone just pick up Not Enough Items? Has no disadvantages otherwise. And what interests me most: Why do some modpacks have both mods in it at once? What's in it?

And finally: Can someone tell me why Not Enough Items crashes the game for me? It should actually be compatible with all mods.

Version: 1.7.10

TMI is the outdated predecessor and NEI is the new improved alternative.

To judge what the crash is a crash log would not be bad.