It's not only good for buzzing, it's good for young musicians developing ears, because if they're not hearing it in their head they won't be able to buzz it with good quality. I enjoy using it because I can change the resistance and trick my fingers in to thinking I'm acutally playing
Well I know when I've performed in the past, if we're going in as "exhibition" even at a competition it doesn't matter if there are judges there, since we're in exhibition, we don't get judged or scored.