The first thing I want to say is this: don't ever let everyone else's opinion shake you away from something. I've read a lot of negative reviews about this process and I have not felt negative about it yet, in fact it's been very timely. They keep reminding you of their "transparency" and that they believe in not wasting anyone's time.
I applied through the website and was contacted the day after. I had a date and a time for a 30 minute phone chat before noon.
The 30 minute chat was actually more like 45, the gentleman I was talking to was very friendly. By the end of the interview I felt really good and he said he would "talk to his team" and either he would "send me an assignment" or "let me know otherwise". Three hours later I was sent the assignment.
The assignment was rigorous and I spent a great deal of time on the first question, but it was okay because the last two questions were easy to find online and through the website. I turned my assignment in, and the next morning I received an email from the same recruiter asking if I could go into the office for a 3 hour interview the next week, again stating if that at any point they felt as though the position wasn't a good fit for me it would be cut short.
This interview was not intimidating and I enjoyed meeting the three gentleman. Very standard interview questions and and it's clear what kind of candidate they are looking to hire.
No offer yet, but I hope to hear back from the company. All in all, I've not felt the process to be impersonal at all.