KLC & KRC works fine for us in .20. I've seen a few reports here and there of people having issues after various patches, but we never have. Yes, the agent upgrades and updating your KLC client-code version are a must.
I'd say give it a go - 220.127.116.11 is really looking great for us overall.I know a call out a lot of bugs, but what I suppose gets lost, is that for the most part, things work. If you read between the lines in some of my posts, then you could easily assume the whole thing is broken -this is not the case. Yes there are a few niggles but I would never go back to 9.2 or earlier.
If in doubt, do your upgrade on a week night that isn't a Friday - therefore if you have issues you can get onto support the next morning.
I installed 18.104.22.168 last night, ans had two things that were out of the ordinary.
After patching I had 3 or 4 Kaseya Services unable to start, one of them was the Event Service.
Reapply Database Schema fixed it last time, so ran that again, and indeed things were fine and dandy, but...
This morning our Kaseya.SecurityCenter.AV.Service.exe process on our VSA was taking 5 GB of memory, while a maximum of 300 MB is normal. I have to say we see this happening once every 2 or 3 weeks anyway, so it's not directly related to the patch, but did trigger the condition. Restarting the Kaseya Antivirus Service service is a simple solution to this and brought the memory usage back to normal values.
I upgraded to 22.214.171.124 yesterday and no issues so far. Custom machine roles still don't work which is annoying when using the new Live Connect User Portal...been logged for a while now.
Regarding some of your comments.
Showing why a machine is out of compliance.
I have a ticket to show this in the UI. With the new Kaspersky SDK, we are able to get more details on this and I plan on adding this to the UI.
We schedule tasks on these, since when an agent comes online, we expect you would want the task to run. We could possibly look into an option for this not to happen, but it is tricky, since some jobs happen automatically to update the agent license and status and such.
Adding alerts to agents without KAV.
I am assuming you mean in the Antivirus > Configuration > Alerts > Edit/New dialog. I Made a ticket for this.
On the Antivirus > Show > Machines page, this can be filtered to not show uninstalled machines. Plus this should be a good solution to add alert per Machine Group / Org.
On the issue of the machines going away when you sorted a column. If you get this to happen again, please let me know what column it was. I tried to replicate in house and could not.