Well five out of ten Go is at least 2X faster (that's significant enough to me). In any case, probably the difference won't be noticeable since the bottleneck for most websites is the database side.

But compare either, with, say, Python or Ruby and the difference is more than lost in the noise.

I'm pretty sure at least one of those tests Racket does better at is essentially a GC benchmark. Go's GC is still fairly weak.