Other than claims by the author of G-WAN, I've yet to see anybody claiming that G-WAN outperforms Nginx. I also cannot find any evidence of anybody using G-WAN in serious production. I could be wrong of course, but every time I've inquired about it, nobody responds. I also cannot find any kind of community around G-WAN.

Also, it seems that a lot of the "performance" in G-WAN is thanks to its microcaching feature. When it's under high concurrent load, it caches requests for about 1 second. I suppose it's useful on public cacheable responses and useful in benchmarks, but does this really count as "faster" in the sense that G-WAN is a faster system overall? I don't know.

That being said, G-WAN has many interesting aspects indeed.