This is definitely a Vocal mic used in live situations.
It is a Vocal Condenser mic with a Cardioid Pattern.
The best thing about this mic is the both the warmth and the clarity it delivers in a live setting. it is excellent for any kind of vocal style and is a lot of fun to use. Being a Condenser, you can really use the space around the mic to get awesome dynamics (unlike a dynamic mic which you usually have to be pretty close to be heard). I am also a pianist so I find myself unable to keep my mouth right in front of a mic all the time. With the BG 5.1 its a lot less of a problem being heard an playing.
The only problem with this mic is the traditional problem using a Condenser live, feedback. In all honesty though, there is little chance you will get any if you set it up correctly (ie not to close to you monitors and not too close to any other sound source besides your voice). If you set it up right, people will really notice.
I paid $100 for this mic used. Unfortunately I don't believe they are in production anymore so you have to search around for a used one. $100 for a nice clear/warm mic with a lot of presence is not a bad deal at all.
I own a few different vocal mics but the main one that contends with this mic is my Shure Beta 58a. The BG 5.1 is my main vocal mic, but if I am playing with a loud rock band on a medium to small stage, I usually use the Beta 52a. Its a safer bet when you have to worry about feedback. But if that's not an issue, I definitely go with the BG 5.1. Another setup I like is to bring both. The BG for my clean vocal and the Beta 52a for effected vocals. This ensures my clean voice is well heard and my effected vocals don't feedback (especially when using distortion).
I would definitely buy this mic again. Someone was selling a pair of these in great condition for $120 and I passed due to lack of funds. I am still very sad about that.