yes, the version of naviserver in bitbucket https://bitbucket.org/naviserver/naviserver
is the version we use in production. With the config file openacs-config.tcl (on bitbucket) it works pretty much out of the box with OpenACS. We switched to naviserver about two years ago and developed a small layer for the openacs. With this and a recent version of xotcl-core one is also ready to use naviserver with XOTcl 2/NX (http://next-scripting.org/
Below are some long-term statics from our production system, where one can see how the resources went down and the performance improved. All data is from the same hardware. In the the last two years, the number of views/day more than doubled, while the overall response time was cut to less than a third (even though the database size went up, we have added recently much more rather complex queries for workflows, plagiarism checking, lecture casts, etc.). We have now more than 120.000 learning resources, more than 5.000 courses per year. Performance-wise, XOTcl 2/nx helped a lot, but finally, it is hard to say, how much each piece contributes. Due to the reduced resource consumption, our next production machine will be significantly cheaper than the previous one (will be in use in oct).