After using it for about an hour, the Lorex version is better. I am running Catalina on a iMac Pro and the main differences I am seeing are:
SmartPSS crashes often when closing the application while the Lorex app has not crashed at all.
SmartPSS issue when moving window from the iMac display to an external display that has a lower resolution. When I move the window (or even open the app) on the lower resolution display, all of the camera views are 'zoomed' in unless I move the window back to the iMac display. This issue does not occur with the Lorex app.
That being said I have removed SmartPSS as the Lorex app is more stable on my machine.