Hassan was my guide when I joined a few months ago.
As you said, very low key but always nice and willing to help. I had no problems with our dealings and called him several times during the decision/buying process. He always returned calls promptly and was willing to call me on his days off, which I declined. When I visited VWL (after buying), he offered to meet me there even though it was his day off. Again, I declined but thought it was a nice gesture.
I thought he was knowledgeable and good on follow through. He was a little surprised at the information I already knew from reading this board, so he didn't have to "sell" me, just clarify a few points.
I have no problems with having him as my guide.