When it comes to any supplier, Chinese or not, we would never recommend using a transfer service and for very good reason. You have absolutely no recourse to any money back claim when using that type of service. Of course it's ultimately your choice if you are happy to take the risk, just understand the reality of it the transaction turns out bad.
In regards to being an Alibaba Gold Member. Memberships on Alibaba are paid for, they aren't earnt by good business practices, so I wouldn't personally put much credibility in that personally.
One other note of caution. If it's branded items you are considering buying from a Chinese supplier, then they will be fake. 100% absolutely fake, no matter what the supplier claims.