Triple Buffering has a high GPU memory cost associated with it, so sometimes it can actually kill your performance if the game you're playing is already working your card fully, but as Here there are literally no down-sides.
Triple buffering gives you all the benefits of double buffering with no vsync enabled in addition to all the benefits of enabling vsync. We get smooth full frames with no tearing. These frames are swapped to the front buffer only on refresh, but they have just as little input lag as double buffering with no vsync at the start of output to the monitor. Even though "performance" doesn't always get reported right with triple buffering, the graphics hardware is working just as hard as it does with double buffering and no vsync and the end user gets all the benefit with out the potential downside.
If you have the hardware requirements to actually use triple buffering then (in my opinion) you should definitely use it.