iancjThey (Antlion) have a very informative page on their website discussing the tradeoffs between omni- and unidirectional mics. In addition to the pickup pattern, omnidirectional mics also have better sound quality than uni-s. If you have a quiet room to record/game in, then the omni- mics will sound better, but loud mechanical keyboards, squeaky gaming chairs, and annoying roommates/family make the uni-s a better choice.