The latency...
It depends on too many factors:
- internal ffsdhow input/output buffers (you can try to play witt them on ffdshow properties page -> avisynth -> buffer back/ahead but I'm not sure it'll change anything)
- video renderer input buffer
- threads count in SVP (in Avisynth actually)
- SVP settings => one frame processing time (which can be rather big value like 150 ms or something)
- may be the latency is a little bigger with GPU acceleration turned on
so in a real world with 10-15 threads the latency is around 0.5 seconds at least the latency between frame input in Avisynth and it's presentation on screen, and I have no idea how to measure full latency