Is RMON (as deployed on cisco switches and routers) able to monitor traffic flows as NetFlow does?
Are there any devices that have full RMON support (except NAM)?
Cisco NetFlow or RMON2:
NetScout manufactures RMON2 probes that need to be placed strategically like sniffers. IMO, probes are most potent at traffic analysis since they're dedicated hardware appliances, at the tradeoff of being expensive to deploy to achieve comprehensive coverage and taking up SPAN sessions. NAM is in-between. NetFlow is "free" and relatively the most convenient to turn on.
Network General's Distributed Sniffers seem to support RMON and export NetFlow-format stats as well.