Which microphone is right for you? Guy Cochran, of dvestore.com, has created a solid microphone comparison. Shot on a Canon 5D, he uses a professional multitrack field recorder in a noisy environment with everything from a lavalier to hypercardoid to shotgun microphones.
Watch after the link.
The most interesting thing for people who don't know about microphones is to hear how much of the room is picked up with the shotgun mics. Most people believe that shotgun mics are the best in noisy environments but you'll hear for yourself that this is not the case.
Even the simple lavalier can be quieter than a shotgun and it's a lot easier to use – especially when you don't have a full time sound recordist.
My experience is that you can't have too many mics on a shoot. Not only do you need to be able to match the mic to the scene (just like a lens choice) it's wise to record with more than one mic. You can cover a problem with the video but if the sound drops out you're out of luck.
I find that the best sound is sometimes a mix of two mics and it's great to have that option in post. Most digital recorders can be used with two microphones, one fed to each track. If you need more than two tracks the Zoom R16 for around $400 is worth looking at.
Let me know what you think. Did the shotguns sound like what you imagined?