The musical was better in my opinion. I did watch the musical before though. 

The character were shallow and self obsessed (but they're teenagers so idk) and were the same from start to end. Jeremy didn't truly learn anything. In the musical the characters were much more relatable and lovable. The musical isn't my favorite by all means but its far better than this. 

But I will say, the book is very funny and I laughed a lot. Though some of the jokes are pretty outdated, it's still funny overall. And they're were a few very relatable moments in my opinion.  Also I know it's an older book and it's supposed to be over the top statire but the way they treated the girls was gross. 

It's could've been way better but it's not the worst thing ever. It was very quick and funny. The ending was terrible.