A month ago I modified play/record resolution on all 8 cameras to 5Mpx, with a fps of 15 and bitrate as follow:
Main stream (used for playback on browser, but also on NVR's attached monitor when full-screen) - 16 Mbs
- 8 cameras x 5Mpx @ 15fps, 2048 Kbs
Substream (used for playback on browser or EZVIZ app, but also on NVR's attached monitor when multi-screen) - 4 Mbs
- 8 cameras x VGA @ 15 fps, 512 Kbs
Event stream (used for motion recording only) - 76 Mbs
- 6 cameras x 5Mpx @ 15 fps, 10240 Kbs
- 2 cameras x 5 Mpx @ 15 fps, 8192 Kbs
Incoming bandwidth = substream + event stream = 80 Mbs.
Outgoing bandwidth = main stream = 16 Mbs.
So right now I'm using 8 cameras @ 5 Mpx making use of full 80 Mbs of the DS-7608NI-E2/8P NVR, recording being done by event (motion, intrusion and line crossing). Seems to hold up pretty good till now and hope it will last for years.
The main advantage of 5 Mpx recording over the 1.3 Mpx or 2 Mpx would be the ability of zooming-in while doing the playback of recorded video to get the most out of camera's sensor. Basically, a simple one-step zoom-in while doing recordings playback will show up the whole resolution of camera's sensor, without any digital interpolation.