For the software, nothing is as good as IS Boxer.
Although a lot of the functionality exists in HKN, if you're willing to learn/write your own scripts.

From people who have used both, Pwnboxer is easier to use when beginning.
But having not used it, I cannot say how it is easier than running an IS Boxer wizard and having a hotkey for follow, invite the party, and auto assist without needing any knowledge of warcraft macros.



Many of the features in Pwnboxer seem to be weaker versions of IS Boxer features:
Repeater Region (ISB) vs Mouse Clickmapping (PB)
With a Repeater Region, you can have a modifier held when the mouse enters the region, you can decide which slot receives the clicks, you can have a group be the target so two of your five toons receive the clicks... you can use a mapped key to modify how the repeater region works in play.
Mouse Clickmapping is like a Repeater Region that sends the clicks to one target.

Clickbars (ISB) vs Dockable Clickmapping (PB)
The IS Boxer feature links to a Mapped Key, which can do a vast number of things ranging from adding a DPS toon to your healer group, so they'll also heal... to activating/deactivating another mapped key, to the straight click here and this key is broadcast (which is what you can do with PB's Dockable Clickmapping).

Video Feeds (ISB) vs Magnification Region (PB)
I'd rather have a video feed, from the slave unit to the master than an area of the slaves window which is larger on the master's screen.
This is about the only feature that the two have, that PB had first.
Although Video Feeds are far more powerful/flexible than the simpler feature of Pwnboxer.



Check out the respective forums for the two programs.

Lax and Tim are both fairly responsive to questions on how to get their product working.
Lax however will push out updates much more frequently (50x as often); someone wanted to play Realm of the Mad God (a Flash or Steam game), and now there is support for playing any Steam/Flash game with IS Boxer.
The list of games that you can use IS Boxer for is very long; PB works with a lot of games, but not nearly as many and if it doesn't work there's not much chance PB will support it; conversely, Lax has adapted IS/IS Boxer to work with numerous games.

The IS Boxer site has an extensive wiki to look up things.
There is a massive number of guides from its users, on how to do things in a multitude of other games beyond just Warcraft.
There is an IRC, which gets much faster support, than any other boxing program...