... you are lucky. As we approach Chinese New Year, the entire country will effectively shut-down. Had the company you ordered from been a bit slower, you may not have gotten your items until March. For 2017, Chinese New Year starts on January 28. The holiday lasts 7 days and preparations start a full 7 days before.
Everyone has good and less-than-good experiences with China procurements. In my posts, I recommend ordering no later than November 30 as a rule-of-thumb.
Additionally, for U.S.A. customers, past experiences with China as a "favored Nation" status may change dramatically in 2017 - be aware. I am always pleased when items I ordered internationally arrive on-time and in good condition. For many newbies that are unfamiliar with the highs & lows of parts procurements, eBay may still be a better approach if the dealer is located within your country and ships directs (that is, not drop ship). For example, a local Atlanta man sells ESP8266 modules on eBay at a reasonable price and he keeps a local stock of these items. Therefore, the link between my order and the order in the mailbox is simply the USPS ... thereby avoiding International shipment and Customs.
Play it Smart
If you are going to order one module from China, consider ordering a minimum of 2: one for experimentation and one to keep pristine (after initial checking) to use to be a tie breaker when you are trying to decide between code and hardware during a problem. Absolutely nothing beats having known-good working hardware when a software problem is suspected, but not certain.
Personally, I generally order in quantity of 2x for more expensive items (the $10 category) and 5x for modules in the $4 - $9 range if I know that the parts will be utilized. Be careful, many Chinese vendors on AliExpress will change from "free shipping" to a fee-per-item when the Quantity box is increased passed 2x. For $1 items, doing a full AliExpress site search will often turn up a 10x quantity with free or very reasonable shipment costs.