Happy just finished my S3->Gold Boost. He was very quick to initially respond to me and within 24 hours we had the transaction complete and the service started.
Despite me giving him a timeline of 1 month (before the season ended) he completed my boost in less than 3 days. He was very friendly, open and efficient. His price was also quite a bit cheaper than any of the professional sites I've looked into.
I'd definitely recommend him for anyone looking to hit that gold tier for the nice end of season rewards!