On: Why Ruby/Rails speed doesn't matter?

[mkull]

Just to clarify a bit, he is being conservative, and it's 5 req/sec per mongrel (4 mongrels), which would come out to 20 req/sec for the vps setup.

[nickb → mkull]

And you can easily add another slice to this setup...

Author definitely has a point. If you're picking a new language for your project, I wouldn't worry about Rails' performance at all.