My thumb shifters came from SJS, I was following the lead of someone on here, can't remember who. I went for them cos the old shifter/brake lever combos were getting a bit knackered and I don't like indexed front gears. I have bar end changers on my road bike and love them.
The Avid levers and BB7s are fantastic. Claud is my favourite bike and his new kit (which has been in use for a while now) just makes him better. I'd love to do a long tour on him one day.