From my experience, I saw no difference using a Sound Blaster Live! Value card (not GSIF) or the Echo Audio Darla24 (GSIF) when it comes to polyphony and latency. Both cards were able to achieve 160 voices of polyphony on my Compaq Presario 7000 PIII/800 with 128MB RAM. And like I said, the latency was not noticable to me. But then again, I\'m just an amature. (hehe)
My samples are pretty simple though. The only ones I used that might cause GS some work were the GigaPiano and Bob Clearmountain Drums II. Other sounds I use are from the GM500. I might have a different story if I tried to load other samples that are much larger.
The place I did notice a difference between the two cards when when recording into the sound card from an outside source. The SBLive! Value card is very noisy, so now I\'m back to the Darla24 only.