I'm generally not a big fan of on-camera stereo mics, but this unit seems intriguing:
bp-4029 (http://www.bhphotovideo.com/c/search?Ntt=bp-4029&N=0&InitialSearch=yes)

Review:In Review: Audio-Technica BP 4029 Mic (http://www.dv.com/article/92292)

While not exactly cheap, it's not a ton more than a good mono shotgun mic. Anyone have experience with this? Your thoughts?

I've had this mic for a couple of years and really makes a difference in recording. You get good audio throughout, even when moving and turning away from the speakers. It used to be an AT835ST. I love the mic.

I have used the BP-4029 for a while but it was extremely wind sensitive. The sound was great those times it didn’t took up wind or movements in the air. I used a large high-wind fur in it. So I went back to a Sony mono mic.