Story-wise and character-wise, GTA V blows GTA IV out the water. The protagaonists Michael and Trevor are great characters but Franklin seems to lack the depth of the other two. As for the setting and work gone into the map I'd put it at number 1 for effort. The place really feels alive and real because of all the little details. Of all the GTA's I'd put it at least number 3 on my list, close behind San Andreas if not equal to. Still doesn't beat Vice City for me though.
Let me put in another aspect. As some one who's lived in California the details are practically insanely accurate, from the beaches, LAX, Venice city, the la river, city out skirts, sunset strip, it's spectacular.
Not o mention the game has waves. But honestly for anyone else who lives in la rocks far did an awesome job
And of the 3'characters micheals my favorite followed by Trevor.
As for other GTA's it's top 3 as well.
Now if they just re do vice city as well then omg it would be epic.