It doesn't seem to be much difference in price between the two. The 536 has WiFi so you can monitor from a phone app and if you use an iPhone or a mobile phone that has Android 5 or earlier you can also control it. The 536 has LCN finder and system diagnostics and some other things that makes it a better scanner if you have to search and analyze frequencies and system that are not available in the database or lack the necessary info in frequency listings to be able to program the scanner correctly. The SD card makes it possible to record info and audio and have room for a lot of programming and saved files.
Overall the 536 gives you more for almost the same money.
/Ubbe
