I did a short (poorly done) video on the 16S400 a couple of years ago. The crystals are the 10.7 IF variety, same as Regency and Radio Shack Scanners, and of course it's 8 channels instead of 10. If it's working it should be a LOUD scanner as well capable of filling up a room with substantial background noise.
The specifications many be similar for scanning speed and volume, but it *MAY* also be lacking the UHF-T band if I remember correctly. If I'm not I hope someone corrects me on this.
Anyway you can get the manual for 16S400 I made into a PDF a couple of years ago in <<
THIS THREAD MESSAGE >> while it may not be 100% accurate for the 16S300 it might give you some insights.
I use my 16S400 daily for my favorite frequencies and the one thing I love about this crystal scanner ovey my other sythesized radios is the lack of hiss on the audio.