I gave it a couple days, but pulled the plug on BI5 just now. I, too, had the initial installation issue where the settings disappeared after BI4 was removed - and then couldn't get either running. Fix is to delete the local_Machine/Software/Perspective folder in the registry (you will have to change permissions to 'full control' for admin to remove the 'a1' folder). After I got BI5 running with all the correct settings from BI4 imported, I had horrible console freezing issues. The screen images would freeze and not refresh. Console was still responsive - I could change settings, but the boxes for cameras and dialog boxes would get stuck on the screen. Only fix is to close and re-open console - but that only lasts for a few seconds.
Today I noticed 3 restarts of the BI service "unexpected restart" logged. I also noticed the my scheduled event to toggle IR on a specific camera was not being triggered. BI can toggle the IR manually, but the schedule event time comes and goes, and it doesn't fire.
So, for now, I've gone back to BI4. I stopped BI5 service, uninstalled it, and deleted the perspective software folder in the registry. I then imported the BI4 perspective software folder directly into the registry (from the regeditor). Finally, I installed BI4. It came up perfectly, just as I'd left it before trying BI5.
TL;DR: Not ready for prime time. I'm giving Ken plenty of room to work out his teething issues.