Comment by lispm

It is, the 64bit version is really fast, similar to SBCL. But that's already kind of a local maximum. The GC and the rest of the runtime is better, probably CLOS is more optimized, ... LispWorks does not type check code much, but it has type inferencing when optimizing code.

You can see my benchmarks (the last from 2013) on my Mac:

http://lispm.de/lisp/benchmarks.html