Think of this as playing Quake3 with mouse sensitivity really low, and mouse acceleration on. Personally, as a kb/mouse lover, I'd never touch this thing... sounds more frustrating than even using a controller.
You can't say yuck until you try some of this delicious broccoli. Now eat up.
Actually, mine was shipped from HK on friday, so I expect it heartbeats before Halo2 is in my hands. As to the accelleration thing, have you tried playing Halo 1 with the vert and horiz acceleration cranked? the response time is pretty quick... but then you lose precision... that's what this is supposed to fix. It's not like I'm installing a 3000dpi Razor Boomslang and somehow magically having an unreal response.
Simply put, it's an alternative. I've heard (far too often) from die-hard PC gamers that the downfall of consoles is controls. Now lets just see if that is the case. IF the performance grade (IE response time, accelleration) is the same, will the mouse/kbd be better or worse? I enjoy my controllerS, but I'd like to see the other side of the fence (on an Xbox).