I have the incorrect one (looks just like the one you linked to), but I"m waiting for the one you linked to. (They both look identical, but have different model numbers, and somehow, I ordered the one NOT for the 8100)
However, the INCORRECT one works great!
I love being able to use my upgraded headphones (in ear headset, which I much prefer... the one that comes with the bb keeps falling out of my ears, and doesn't sound nearly as good as my Vibe's)
Works great, tap the hold button, music pauses, and you can make or receive calls, or simply pause your music.
One caveat. you need to make sure to plug your headsets into the adaptor BEFORE you plug the adaptor into your Blackberry, or it won't work. Not a big deal, as long as you're aware of it!
Go for it, you won't be sorry!