I've used JMeter in conjunction with Selenium, Java, and Log4j for logging. I used it before
I ended that contract in August. Its version was up to date at that time.
It was used for an e-commerce site that is specialized in C-PAP or weaving machines in effect. Their max was a thousand people logged in at once. I, of course, pushed the boundaries on that, but it was to test the performance of the website, and of course, I'm had to try subsystems, database interactions, etc.