It is a good product that is robust. They have a free version that makes the value good. If it cost money then the install and plugins would need polishing. But overall it is a good product that does what it says it does. But definitely not for beginners you do need some knowledge to set it up and get it running
The SMP solution is a beast. Each piece is complicated in itself let alone how everything ties together!
There is plenty of documentation online on how to perform a specific task, but you need to pay attention to what VERSION the article is written for. I've been halfway through implementing something only to hit a roadblock since I'm running a newer version and the option the article says to click on doesn't exist anymore...
Centreon does a good job against these products. Of courseCentreon can be free and that is what we used. So it is not quite the same the other products are more polished and support is readily available. But Centreon is still good and if you have some knowledge can work just as well
I have had exposure to SCCM before we moved to Altiris (aka SMP) and SMP does some things in a more complicated way, but there is a LOT of flexibility too. For example, with Patch Management, it's very similar to SCCM, you download the patches you want to install and then publish them. However, with SCCM, you need to have WSUS running on the back end to handle the patch deployment, while SMP does the installs itself. It syncs the patches with the agents and stages the files, and will install them when the maintenance window opens.
Being able to report on the majority of things you want all from one interface, makes it really easy to get the results you want.
Because my employer didn't provide training, it took working with support, reading technical documentation, and just playing around on my own to learn how to do certain things.
I've had a lot of help from the SMP Support staff and they're great people and very helpful!