I've been using DynamicBoxer for several weeks.
This addon has changed the way I play WOW. Before the addon, I couldn't easily change one slot to another toon. I could do it, but follow wouldn't work, assist, etc. unless I change ISBoxer config.

The addon makes changing team members or doing cross realm teams extremely easy.
All setup is done in wow and most of it is automatic: you don't have to do anything.

With DynamicBoxer, I don't have to change ISBoxer config just to play with different toons.
To group up with a completely different team, I just log out and back into the correct toons.
To change one toon, I log off one toon and back into the correct one.
When things don't go the way they should, it is a simple command with copy, paste, enter and things are back to working.

I play with 5 man teams. Doing Islands meant I either did one toon twice or just didn't run it with 2 of the toons. Now I can cycle through different toons on different teams.
I would encourage multiboxers who use ISBoxer to give this a try. You only need to setup one Character Set in ISBoxer instead of one per team.