Is there any part of Solarwinds products that can do throughput tests for packet-loss/latency/RTT? Internal IP to Internal IP and/or Internal IP to External IP
Also depending on the level of depth and visibility you need, you can check out products like this one
Can you elaborate a little further what you are looking to accomplish. Off the top of my head, one idea is WAN Killer in the Toolset.
Just trying to monitor various TCP and/or UDP applications end-to-end. Some sites are through MPLS clouds, some through VPN tunnels (xDSL or Cable-Modem), some through T1 circuits.
We need to isolate those hops where packet-loss is a constant issue (along with high latency).
Depending on the type of operations you want to test, another option to look at is IPSLA Manager. You can setup operations from router to route. In situation of an MPLS cloud, since I assume this is not your infrastructure you lose visibility.