I've met a lot of customers who are using open source tools like Jmeter for performance testing. Traditionally, we have tried convincing them to use Zebratester instead - and it rarely works.
Instead of having Zebratester as the "main" product and LTP as a "feature", it should be the opposite. We should support other load tests scripts other than Zebratester in LTP, in this case Jmeter which is the most popular open source load test tool. I think it would open up a whole new market, and it would be much easier to sell LTP and all its functionalities to techies who love their open source.