Quick anecdote arriving in CNX for the first time on a new DTV (workation from Hanoi). Showed them the visa on my phone, IO looked at it, called someone else over to look, asked me if it was my first time entering on a DTV, and stamped me for 180 days. Easy. Might not be too interesting to you...but I kept seeing horror stories of people getting interrogated on arrival and wanted to counterbalance some of the FUD. (Doesn't hurt to be prepared though; I had all the documents from my DTV ready on my phone.)