I have some servers running for my network on VPS's. I don't mind using ssh for everything, however it would be nice if my admins could manage the servers too.
Now before I want to install this I want to know if it's worth it.
To see if it's worth it I need to know the following things:
How much ram does pufferpanel use? And how much CPU? (the latter is complicated, I understand)
PufferPanel v0.8.x is written in PHP, and it uses about as much RAM as a normal PHP program would. You will need nginx and PHP-FPM installed and running as well.
I cannot estimate either of those because it all depends on how many people you have using it, your system, and how hungry the pufferfish are today. I can guess that PufferPanel + nginx and PHP-FPM might use about 20MB of RAM, but that's just from me playing around on my machine with a low load. Your experience may be entirely different. "How much CPU" is not something I can accurately quantify. I really don't know how to answer that question.
Scales, the daemon, is a bit more resource intensive and is written in nodejs. Its resource usage also depends on how many servers you have running. On my machine it looks like it's using about 40MB of RAM at idle. Scales might use the CPU a bit more since it's running constantly, but again I can't accurately tell you how much.
I highly suggest you just try it out and see.
Building on what @puffrfish said, once installed you could install a resource monitor like htop. It's click friendly even in ssh and I haven't had any problems with it.