I've applied for a position with them, took a while (3 weeks or so) until I had a response for my application. But eventually it did arrive. I went on to take the first screening tests, and passed (first try) on the first qualification exam. Unfortunately I failed my first try of a second -- more specific -- exam and will be trying it again tomorrow. Hopefully I will soon come back with good news.
One thing that did bother me though was that I was mostly left to my own devices. Don't get me wrong, they provide plenty of helpful and useful materials/information, but when it comes down to direct communication, they do seem kinda lacking. I have 3 unanswered emails that I have sent so far, all pretty straight forward and to the point, mostly minor questions about one thing or another. Surely it wouldn't be that much of a hassle to reply. At least I did not receive any of those generic, auto-reply and usually unhelpful emails. Maybe they don't bother with candidates that are yet to fully qualify for an opportunity.