On the subject of Curb vs Seinfeld, I prefer Seinfeld by a wide girth. Curb gets really repetitive, is very hit and miss, and always seems to follow the same structure and flow. Larry does something, somebody does something, Larry does something awkward, and they do something awkward back. I will go from laughing my butt off like from the Shaq episode to just staring at the tv, wondering when I should laugh.
On the other hand, there's Seinfeld, which is consistently entertaining, varied in theme and subjects, and social observations. It's the PG version of Curb, but it's far more nuanced and interesting. Somehow, Curb feels more cartoony and less realistic than Seinfeld and feels like "famous actor of the week" fare. I dunno. I really like Curb, but I don't love it like I do with Seinfeld.