This page is of course from a professional load tester's perspective, rather than the project manager's view, who may have to pay for it!
I have used LoadRunner for more than 10 years but recently I have been at a location where LoadRunner just wasn't in the budget. So we used TestPlant Eggplant (formerly Facilita Forecast) and JMeter. These tools are ok, in fact you could say they are better value for money than loadRunner, but this is only because they are cheap or free. Mind you, I don't want to put these two tools down here, not at all. They are valuable contributions to the space and I have been working commercially for 2 1/2 years with only these tools and we have kept commercial scale sites up and running.
However, if you can run to the expense of HP LoadRunner, then it really is well worth it. And here's why:
NOTE: I'll compile this page as issues present themselves along the lines of a blog. I am currently replacing my eggplant and jmeter workflows with LoadRunner ones. This will be a progression over the next few months, particularly with the jmeter CI work.
1. LoadRunner now supports CI with Jenkins
2. eggPlant often reports misleading numbers
3. eggPlant doesn't fully support long test runs
4. LoadRunner logging is great
5. LR runs for days...
6. LR analysis compares runs
7. LR analysis has some great facilities, such as time to first byte breakdown
8. LR allows users to be ramped up/down on the fly without stopping the test
9. LoadRunner has complete control over graphs, with comments and 3D and many other options available