Both of the HST films have problems. This film's problem is that it is too "screenwritten" (Lazlo replacing The Brown Buffalo, "Blast" Magazine replacing Rolling Stone, etc.) and lacks the weird surrealism that a drug-fueled observation of American culture at the end of the 1960s deserves, if not requires.
It does play a bit like Caddyshack, as someone else pointed out, and it's hard to get really invested in the characters. And if you love HST as much as I do, you really do want to get into the characters and in to the story, because it's as important as it is funny. Where the Buffalo Roam is, for the most part, silly. It comes off as more a bunch of sketches than anything else. I did like Bill Murray in the part. The problem is the script, more than anything else.
Fear and Loathing in Las Vegas, by contrast, does well with the surrealism and depravity but fails to make the full point I think Thompson was trying to get across - the decadence and over-the-top performances (especially of del Toro) are distracting, and really all of this is supposed to be about the death of the American dream, and the end of what was (to some) the best decade on record, or at least the one where people thought, for a time, they could make something of American life. Both movies hint at this but don't go into it enough, in my opinion.
Where the Buffalo Roam captures a little of the sadness and the creeping hopelessness of the early 70s (along with an indication of the hangover awaiting that generation in the 70s), but both movies fall far short of Thompson's books and writing in my opinion.
I was particularly saddened that both movies left out the "We're looking for the American dream" bit at the taco stand, because I think that was important, and the F&L Vegas story seems decontextualized without it (in terms of having a fairly serious (and sad) point under all of the humor and excess).
In any case, both movies are worth a watch but ultimately unsatisfying. Thompson is still best read. I think a good film about HST can be made, but the right person needs to be at the helm.
Richard Linklater or John Sayles, perhaps...someone who isn't going to miss the deeper substance underlying and buttressing the humor. That being said, there are far worse movies you could be watching than either.
And like Thompson, it still hasn't gotten weird enough for me.
