I have used Aliexpress in the past for more than 50-60 orders without having serious problems, except their below average online help service. Unfortunately all have become problematic from late June onwards.
On 28/6/2016 a seller gave me a refund of 62,50 euros for an order and I was eagerly waiting for the money to use to on another order. I was waiting and waiting and waiting. I contacted numerous time the terrible online service and I always had the same answer "The refund process takes 3-15 working days to complete, please waiit a little longer". Well guess what... the 15 working days have already passed and today I received the outrageous answer that I will have TO WAIT ONE MORE MONTH (!) to see the money.
Obviously ALIEXPRESS runs under financial problems. STAY AWAY at any cost because you gamble your precious money on this site.