Best Re-Straming Performance

[VDIEng]

I have 38 IP cameras (Panasonic WV-SC385) that output 720p with G727 or G711 audio in two broadcast formats.
1) RTSP using RTP encoded with H264
2) UDP using RTP encoded with H264

I have 170 clients with Amino 130H IP STBs that can select the independant cameras as channels. The limitation of the STB is that it must see MPEG TS instead of RTP. So I am intending to use VLC to "reflect" (re-mux) the stream with no transcoding.

I currently have one server, a Dell PowerEndge R310 with an Xeon 2.4ghz 8mb cache and 4gb of RAM running Fedora 14. I have plenty of budget to either upgrade this machine or replace with a more powerful unit (eg R410 Dual proc) if required. I would like this one server to be able to restream up to 15 streams. There are multiple gigabit NICs. I would like to ingest on one NIC and rebroadcast on a 2nd NIC (EG read on eth0, sout to eth1). We would like to run the cameras at 8mbps.

So my questions are as follows:
For best performance should I run the camera in RTSP or UDP mode to restream it?
Any estimations as to the number of streams this current configuration will handle?
How can I use multiple NICs so that I do not need to create an additional inter VLAN route on my managed switch?

Below is the base of my restream command line, how can I modify it for better performance?

vlc -vvv rtsp://10.0.X.X/MediaInput/h264 --sout "#udp{dst=239.0.0.6:5004,mux=ts}"

Thanks,

Tim