While I strongly disapprove of both drunk driving and reckless driving, and I don't drive after even one drink, the focus of the sobriety checkpoints and the speed traps is on revenue and not safety. If a driver is sober enough to use an iphone to get around them or cautious and alert enough to adjust speed based on those alerts, I'm okay with that.
DWI/DUI checkpoint HAVE to be announced in advance. (per USSC) The police publish or announce in the weakest way possible so they don’t have mass public knowledge.
EVEN IF SOBER, it is good to avoid such checkpoints for the sheer nusance avoidance. YOU HAVE to avoid far enough in advance to not be subject to the chase cars police have for the purpose of chasing down u-turners (see “ya all have something to hide?”)