The Samsung Galaxy K zoom has two main video modes - 30fps and 60fps. You'll probably be doing most of your shooting at 1080p, but you can drop down to 720p if you're concerned about file size, e.g. if it's a video you intent to send as a file rather than upload to a video sharing service.
Speaking of which, popular video sharing services such as YouTube and Vimeo only support 30fps videos so showing off your 60fps footage will be quite limited as an option. YouTube recently announced they would offer native 60fps playback, but that feature hasn't rolled out for everybody yet (us included).
Anyway, 1080p @ 30fps videos are captured at 17Mbps bitrate (the same as the Galaxy S5) with two-channel audio with 256Kbps bitrate and 48kHz sampling rate. 1080p @ 60fps videos bumps the total bitrate to 28Mbps as quite as expected the number of frames doubles.
To put that into easier to understand numbers, half a minute of 1080p @ 60fps eats up 100MB of storage. 30fps videos take up around 65MB instead.
Videos hold the framerate steady with no dips but in 30fps videos you'll notice some choppiness with fast moving objects. That is inevitable and the reason 60fps exists - fast motion looks a lot more fluid, so depending on the scene the extra storage may well be worth it (as long as you keep in mind that YouTube will downconvert them to 30fps).
Videos have no visible noise and the amount of fine detail is good, though we've seen sharper videos (again the Galaxy S5 comes to mind). The softness becomes especially noticeable near the borders of the frame.
The dynamic range isn't great either, the Galaxy K zoom under-develops shadows and keeps highlights artificially low so it doesn't use the full dynamic range of the video format. The result is that bright areas (e.g. clouds) look blown out even though they aren't at maximum brightness.
You can download a 1080p @ 60fps sample since we couldn't host it on YouTube.
We put the optical image stabilization of the Galaxy K zoom to the test:
And here it is but this time with 10x zoom to make things harder:
Here's one more zoom video. It stops at 10x (the limit of optical zoom) and then again at 20x (maximum zoom). Also this was shot on a quiet terrace so try and listen for noise from the zoom mechanism:
The Samsung Galaxy K zoom is not part of the 2160p-shooting crowd, but then neither is a photography-oriented Nokia Lumia 1020.