If possible, I'd also like to see a simulated demo. "Watch users interact with your site" is very intriguing, but I'd like to see that in action, even before I commit to the first-is-free trial.
Edit: Expanding on that -- I signed up to see what the testing experience is like, and I see you guys have a stock website so you can confirm a tester account as legitimate. Why not take an example video from this process (one of yours, or maybe a tester's, with permission) and provide that as a demo so that people can see exactly what they'll be able to expect out of their site's review?
As an aside, out of curiosity, what's the point in having varied pricing plans if they all cost the same per unit? You have '5 for $50' or '10 for $100' or '15 for $150' -- why not just say "each test is $10" and let us choose the number of tests we want?