If he takes long to cum?!

I'm in an LDR and I just somehow remember now the last time my SO and I had sex and he literally took more than 30mins and then he cums...he's more experienced than me...
Is that good thing or bad?
I've heard stories of guys cumming in less than 10min and then there's mine! Over 30mins and he cums!! 
Is this normal?  Help, I need to know!!