Can anyone recommend a microphone suitable for a video surveillance project? I need one that can effectively capture ambient sounds, ideally from distances of up to 8/10 meters. I've been researching online and the INMP441 seems to be a good option, but I can't find any tests on YouTube that show its performance beyond 30cm. Additionally, it's often mentioned that it's capable of filtering out ambient noise itself. Another option could be the MAX9814. Any opinions?
The MAX9814 breakout board has lots of options so you can vary the setup. If you need more gain, add an additional amplifier stage. Any filtering will be based on what, exactly? Try it!
The issue isn't distance. It's the loudness hitting the microphone. 
There are 2 issues - Gain/microphone sensitivity, and noise. Acoustical noise (a dog barking or a truck driving by, or any "unwanted" sound) and electrical noise can both be problems.
I have a SparkFun BOB-12758 microhone board and my main issue was electrical noise. I wasn't recording audio, just looking at the Arduino's analog readings... I wasn't getting any good readings above the noise with my TV on at "normal-quiet" volume. When I turned it up a little louder than I normally listen, I could see a difference. ...I have an SPL meter and I programmed an SPL meter with the Arduino, but I didn't seem to make notes of where the dB SPL level overcame the electrical noise.
It was worse when I powered the Arduino & microphone board from USB. (USB power is notoriously noisy.) When I powered it with a separate power supply the noise was lower.
Since this is electrical noise, higher gain wouldn't help... It would just amplify the noise along with the signal. But a more-sensitive mic would give a better signal-to-noise ratio.
Noise filtering is NOT trivial. It's all about signal-to-noise and sometimes noise filtering is impossible. (Pros still record with good equipment in soundproof studios.)
Microphones are linear... Their output is directly proportional the sound level. Except at the low-end you are limited by noise and on the high-end by clipping (where the amp/preamp can't put-out any more voltage).
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