The version of Keyclone which got an ok, is much older then the current version. The current version has added mouse broadcasting, PiP swaps, key remapping which allows FTL etc, these features have never received an ok.

That said, all of the major software options are fine to box with. It is a preference on what you prefer, one or another. There are numerous players using IS Boxer on this site, and I have yet to hear of one being banned for using it. The same goes for Keyclone, HKN, GC-Pro, PB, Mojo, AHK etc.

In my opinion, IS Boxer is by far the strongest boxing option, although everyone has their opinion on this.

You have the option of "action target groups", which are preconfigured groups of toons and can add or remove toons from these on the fly. ATG's can be the target of mapped keys or repeater regions. Let's say, your repeater region is broadcasting clicks to all members of the "Healer" ATG, similarly your click spam macro is sending the clicks to all members of the "DPS" ATG. You could have a mapped key, which removes the Priest from the Healer group and adds them to the DPS group. Then continue to nuke stuff, and maybe switch back on the last boss.

You have repeater regions, which are areas of the screen where mouse broadcasting is on, if the mouse is in the area, and off as soon as it leaves the area. You can use this for Grid/Vuhdo/Healbot healing, but also to click spells or macros on all your bars. I use this for my hearthstone, jamba item bar, a few macros useful for dailies and of course the Grid frame for healing.

You have mapped keys, which can have a hotkey to activate, target toons by name or slot or action target group and have actions which can be macros or keybinds. But you can have a mapped key enable/disable another mapped key, call another mapped key (depending what it does), or do a lot of other options. On my caster teams, when I switch toons the new active toon runs a mapped key which disables mouse click to move on the active toon and enables it on the followers. You can manage Eclipse procs, while mashing the same DPS key etc.

Through mapped keys, we have automatic FTL. When you press a DPS key (1 through =, by default), a mapped key runs behind the scenes. The input is "1". This mapped key, runs another mapped key which causes all of the other toons to assist the active toon, and then it sends "1" to all windows. You can switch to any toon on the fly, and the others will automatically assist the active toon. You don't need wow macros to do this, just drag spells right out of the spell book.

You have the option for sending "next mouse click". I have this enabled on three of my keys: "4", "5" and "Shift + A". I have created three action target groups, one named for each key. And have then added my Druid toons to the "4" group, since they are the only ones who I want to mouse broadcast on a "4" press. When I press "4", each member of that group receives my next mouse click -- I get a mouse target circle in each window which moves as I move the target circle on my main screen. On my mixed team, only the druid on the team (1 druid, 4 other casters) has the circle, not the others. After one click, it turns itself off automatically.

You can PiP swap from one toon to another, literally instantly. The changes are as fast as you can press the hotkeys for each window. You can enable the followers/slaves to automatically follow the new leader on a switch, to strobe follow (a jamba feature) or to not follow at all. I've added the click to move on slaves and taking it off on the main for caster teams, but leave it on for all toons on melee teams.

The sky is the limit. If you want to do it, chances are IS Boxer will let you. The only limitations are, that it has to be doable with either a wow macro, a wow script or a wow addon. At a basic level, the wizard will get you started quite quickly. But you can configure and tweak to an amazing degree, to end up with the configuration that you want.

Take a peak at the guide I have linked in my signature. While it is lengthy, it gives you an idea of what you can do, and how to do it.