Snmp vs ip sla

Since we can get the latency and packet loss information from the cisco rttmon mib after I have enabled the ip sla monitoring from the router, why I still need to get an ip sla monitoring tool from Orion? Can you clarify more? Based on what I understand, the monitoring statistic information will be sending to the local mib file, does it means I just need a snmp tool and display the information using the specific OID will do the same as what ip sla perform? Thank you.