I currently have a p4 1.9 with 786 ram. Would I get more performance to swap out my CPU and RAM for a P4 2.8 with 1 gig of RAM and still use one PC ..........or....... use FX Teleport and connect an old Sony VIAO with and 1.0ghz AMD with 512 RAM to my current setup?
It depends what kind of plugins you want to run. If you want to run software instruments (especially streaming instruments), using another computer via FX-Teleport will give you a huge lift in both polyphony and sample loading capacity. It will really give you a much better boost than upgrading the CPU a bit and adding 256mb of ram.
If you are falling short in terms of software FX like EQ, reverb, etc... then it depends. If you want to run one or two really big reverbs, or really power hungry convolution plugins, again FXT is your tool.
But if you want to run many, many little FX, then it would be better to upgrade the PC. This is because a 100 mbit network will run out of steam trying to buss the audio back and forth and it will not be worth it.
In most cases, FXT is the way to go, but not if your PC is falling short and you need to run like 30 EQ plugins.