Conor hands down. I’ve always hated the name
Calum. I just dislike the sound and look of it...it feels really young to me.
I think Calum’s more likely to be spelled
Callum but both
Conor and
Connor are normal and popular spellings where I’m from. I much prefer
Conor and
Calum over
Connor and
Callum.
I like that both names have meanings related to animals.
Conor feels more mature to me.
I pronounce
Calum with 2 distinctive syllables, I’m from the US.