I'm using NPM to monitor Avaya (formerly Nortel) ERS 4500, 5500 and 8010 series switches and routers. We have ~400 of said devices connected and it handles them fairly well considering I haven't been trained on this product in combination of the fact that management only bought the 2000 interface license and we are still running 10.3. I will mention that it recognizes them as "Synoptics" devices, and the 8010s are "Rapid City Communications". It's not very effective with the current license and management holds the account to upgrade the software. As for Juniper or Checkpoint devices, I am not sure.
Gotta love management.