I watched the first four episodes of Fuller House this last week!
In my opinion, the first episode was very bad, and it explains why the series is getting nasty reviews. The episode was more or less a reunion episode, with non-stop pandering to the original show. They went so far as to have the cast reenact scenes from the original show, with split-screens to compare the original and the remake. Wha...why? If I wanted to see the original cast, do the same thing they did in the original show, I'd watch the original show!
The first episode was also paired with clunky exposition about what the characters have been up to, in the past twenty years. Generally, people don't recap their lives in casual conversation.
Katie: Hey, Michael. I haven't see you in a while. What's been going on with you?
Michael: Oh, not much. I left studying for the priesthood, took a tour of the western United States to pick a new home, moved to Portland, had two girlfriends, married the second one, and now I'm juggling a few careers along with being the househusband.
You see? It doesn't sound natural.
The next three episodes were much better! That's because the show switched over from nostalgia fest to its main premise: three misfit roommates try to raise a bunch of kids. Which is basically the same premise of the main show, but that doesn't bother me. Lots of sitcoms deal with raising kids. The kids are funny, and so are the adults. It's good family entertainment, along the lines of the original show.
I know some people have complained that it has too much adult humor. I would direct those people towards the first season of Full House, where the adults (mostly Uncle Jessie) made some dirty jokes.