Been discussing this with the OH today. He sat through all of AtS with me, which we finished a couple of weeks ago, and tuned in to most of it whilst posting on his own (unrelated) forum.
Obviously we did it the wrong way around and didn't start with BtVS and watch AtS alongside, or even start with BtVS on its own to begin with.
Anyway, since starting BtVS (currently on s2) all he can say is "it's immature" and "it's totally unrealistic", and he usually adds "compared to Angel" at the end.
He hates Xander (let's not go there) and thinks the fact it's set in a high school and they're all kids is the "unrealistic, immature" part. He said he liked Angel, more believable because it was set in LA, the characters were all adults, the storylines were darker, he enjoyed characters like Gunn, Fred/Illyria, Lorne and bought into the whole show more.
Basically, I THINK I'VE RUINED HIM BY LETTING HIM WATCH ANGEL FIRST. I've tried explaining that BtVS does get darker, the characters grow and grow up, a lot happens and that there'd be no spin off show if it weren't for BtVS. I'm at a loss!
Just going to keep watching and hope he tunes in. I agree with him in points but I know where the show goes and he doesn't. That's how you piss off a Buffy fan. (and it's all my fault!)
🙁