Don, maybe you got the negative vibes since your contribution here eventually lead to this thread being hi-jacked and is no longer about MC-012's
I haven't figured out how this whole point-system works; but if it is about someone else giving you points, I hope I'll get some positive vibes also some day...
Anyway, Jacob, as others have pointed out, the 3 capsules are with 3 different polar patterns. The two most used are the cardioid and the omnidirectional capsule. The last one is a hypercardioid. As explained already, the cardioid pattern allows you to "zoom in" on the sound, whereas the omni tend to pick up more room sound, when place at the same position. But there is another thing to be aware of: The cardioid has a proximity effect so that the bass levels will increase the closer you get to the source. Hence, if you want to close-mic your source, sometimes it is better to use a omni mic, since these are very liniear also close up.
I only have the cardioid capsules on mine ("manually" matched), but the cardioid pattern seems pretty wide. I have not (yet) had a use for the omni pattern, although I have another set of omni mics that I could use the day the need should arise.
If you have a nice room to record in, or want to be able to do true stereo recordings in a church or similar, you should go for a matched pair of all capsules. Omni's can also be handy when recording a larger group of people, since you can place them around the mic. Or for certain stereo techniques.
But if this is not your need, I would say the cardioid patterns may be perfectly OK -- but still I'd recommend a matched pair of them.
-- Per.