gentlefury is correct...I use the SpeedTest app first to get an idea of the speed I will be getting
Here is a breakdown of the settings I use...I hope it is not too convoluted

(again, what is good quality is totally subjective for all of us)
Bad Area 3G
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Downstream from SpeedTest = 390kbps
To stream .avi at 624x352 resolution or .mkv at 1280x720 res I set the bitrate in the Global Settings in Air Video at 384kbps
Buffer is ok...does not take long and I only see it at the start of the video
Playback is not choppy but does look pixelated pretty bad
Medium Area
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Downstream from SpeedTest = 850kbps
To stream .avi at 624x352 resolution or .mkv at 1280x720 res I set the bitrate in the Global Settings in Air Video at 768kbps
Buffer is ok...does not take long and I only see it at the start of the video
Again, not choppy but looks ok, not pixelated that bad except for the black areas of video
Good Area
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Downstream from SpeedTest = 1.6mbps
To stream .avi at 624x352 resolution or .mkv at 1280x720 res I set the bitrate in the Global Settings in Air Video at 1536kbps
Buffer is no problem...starts playing pretty fast
Quality of video is pretty good
Best WiFi .mkv at 1280x720 resolution = I set the bitrate in the Global Settings in Air Video at 2048kbps whether it is needed or not
- Picture and playback is fabulous
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