Wrk [1] is my preference. Time-limited tests. Average and standard deviation on latency. And now with Lua scripting.

If you must use an ApacheBench-style tool, at least use the multi-threaded clone named WeigHTTP [2].

With high-performance servers, ApacheBench is a limiting factor.

[1] https://github.com/wg/wrk

[2] https://github.com/lighttpd/weighttp