I should preface this by saying this is my first true Grand Theft Auto experience, but I have had some interesting encounters with the police in GTA V.
First, I think the world is naturally a great environment for randomly encountering the cops. It's a great improvement on just having the cops on your radar at all times, now I have to look around first before I steal a car or etc. Second, I feel like the time period I have to hide from the cops is extremely long, and I'm always uncertain how much longer I will have to dodge them.
Finally, I have had some of the worst luck with cops seeming to spawn at strange places while I'm running from them. I have heard some complaints of how easy it is to lose them when you go off road, but I have had some issues of them showing up out of nowhere off road at incredibly illogical (and inconvenient) places.
What about you? What are your impressions on notoriety and escaping the police?