With SCCM, the client PCs 'phone home' on a schedule to see if there's anything new for them (that's the reason for the delay).

I'm curious about a couple of things regarding PDQ. It's rare though that I need something to deploy immediately. It can be a pain to have to wait on SCCM to do it's thing. If I need to deploy to several machines, I don't have the time to run a script or faff around with another piece of software. We have over 1000 devices, of which over 800 (soon to be over 900 are desktops). I don't want to have to wait around for some time for it to deploy and I don't really want to run a script to get it do to something that PDQ does immediately without having to run a script. We mainly deploy VNC here (though this is now in the build),and it takes 30 seconds at the max to deploy. Once you have set it to deploy, you can come back in a couple of minutes and know it ll be deployed. With PDQ, you can pretty much deploy and forget. It uses PowerShell scripts in the background, so if you're not keen on adding third-party tools you can script it yourself to accomplish the same things.It's all very well there being scripts, but it's not very practical.

RCT has a literal crap-ton of things it can do for you. Install Recast RCT (Right Click Tools, free) and you can right click a collection and force all PCs in that collection to run a Machine Policy Retrieval & Evaluation Cycle. I am told that the main issue with SCCM is that it doesn't install instantly, automatically and as a result it can sometimes take a few hours before SCCM installs the software. We use PDQ mainly here, and it works great.One of my colleagues has been trialing SCCM.

Pdq inventory enterprise