For my purposes, I went with subcards instead of omnis. IME, even the minimal rejection offered by the subcards makes a substantial difference in helping remove some of the audience noise from the recording, while still providing a very open, natural sound. Omnis sound a bit more open and natural, but not so much so that I wanted to give up the slight rejection offered by the subcards. I mainly run my subcards NOS, but have considered running split subcards in the AUD or on-stage, like one would do with omnis. Haven't done it yet, but I will one of these days.