Hi I am dual boxing Champions in there open beta and things I've noticed:

You can open multiple clients on one computer but Keyclone does not work. I didn't try other programs maybe somebody will find something in future but for the time being you can only hardware box.

Boxing in the game is good because the follow function in the game is awesome. Your toons will auto follow in combat, even after zoning and even after you die and resurrect. Also the follow distance is quite far.

Lots of quest I have done so far gave my other toon credit as well which is definitely time saving.

The game gives bonus xp for grouping.

Total customization for powers can really make your team very powerful even if you are only boxing 2 toons because you can tailor choose your powers.

Hope this helps any potential gamers thinking to box Champions Online, it goes live Sept 1 so only a week left to go