TLDR: Flew into DMK yesterday. Short line. Courteous Immigration agent. Great experience.
Full Version: Entered the Kingdom yesterday at DMK airport and had a very pleasant experience. I had filled my TDAC the prior day with my inbound and outbound flight information, was prepared with printouts with additional information if requested (condo lease, employment verification, and so on), and had more than the 20,000 baht in cash available to show, if requested...
The immigration queue was not super long, and I waited about 10 minutes to be seen. The agent was very efficient, courteous, and while I had all of my information ready in a folder, in case there was additional scrutiny, they required nothing other than my passport and my E-Visa (DTV). He stamped my passport for the correct term (180 days), which I confirmed at the counter (always check before leaving the counter).
I would always recommend that anyone entering the Kingdom has entered their exit flight on their TDAC, has cash above the required 20,000 baht, and has paper copies of their visa, as well as any other documents related to their visa. I have heard horror stories from people, and the best way to ensure a smooth entry into the kingdom is by both following all of the rules, and being prepared to show evidence of doing so via paper copies of documents (you never know when a digital issue can happen... trust me, I'm an IT guy).