I can vouch for this guy, I did a transaction with him a while back and received mine in perfect condition.
Any time you've had a good transaction with someone and are willing to vouch for them, go to the Trader Testimonials topic and let everyone know, especially if he's a new trader with little to no reputation yet, positive or negative. People are beginning to rely more and more on that chart as a gauge of whether to trust someone as a potential seller or trader.
Posting here is fine, too, but there it gets more lasting attention.