To rephrase using my experience: "performance aware" Haskell is about as "fast" as Go, but needs more memory, and both are slower than the same Java code - but both are way more fun to write ;). Optimising Go is easier for most people though, in Haskell you _really_ need to know Haskell internals (how to read core and write unboxed code) and understand laziness.

My try of the 1 billion row challenge in Go and Haskell (and C) and comparison to other, fast implementations: https://github.com/Release-Candidate/1-billion-row-challenge...