Other parts of the blog-o-sphere are reporting some issues with the bundling of Guitar Hero III with wired guitars. I'd like to address a different problem that I've had, along with a number of others according to forum posts.
I'd like to preface by saying I really do enjoy the Guitar Hero series (although I have to admit my wife is better at the games than I am), and I've bought 4 games with 4 guitars to date (2 on PS2 an 2 on 360). However, after the issues with the X-Plorer, I'm surprised there was not more quality control with the wireless Les Paul.
I picked up my copy (360 version with wireless guitar) at GameStop at midnight and went home to play. Now, I'm not terrible at the game, and I was having some real problems once I hit tiers 4 and 5 on medium. I assumed I was tired, and went to bed. The next morning, both my wife and I started playing, and once I was able to watch the game more closely, I found that the red and yellow buttons were not registering being pressed. After disassembling and re-assembling the guitar, the problem continued. I tried blowing on the contacts a la NES cartridges circa 1988. While the responsiveness improved, it was still only in the 70-80% range. I exchanged it for a new guitar, which seems to be working in a 95% or higher error range, which is far more acceptable (though still less than ideal on a game that requires such accuracy).
The issue almost certainly stems from the detachable neck's contact system, which is truly unfortunate since the removable neck was generally a good idea. I hope that Red Octane will resolve this issue sooner rather than later. The button problem seems to be appearing on many message boards, so I don't believe my problem is an isolated one.
On an unrelated note, it seems there's some sort of error in the track "One" on medium between the 85 and 90% mark. I at first thought it was the guitar, but having seen the same error with both myself and my wife with both the X-Plorer and Les Paul, I think there's something not working correctly in the track. And it's limited to the Medium difficulty. If anyone else notices this issue, please let me know, but I will acknowledge that I might be wrong on this track error.