[similar personalities] or [a similar personality]

[ansonman]

I have made up the sentences below.

(1) Because we have a similar personality, we can get along well.

(2) Because we have similar personalities, we can get along well.

Some of my non-native English speaking friends think both are wrong. My other non-native friends think both are correct depending on how you think about it.

Do I use the singular or plural form of "personality"? Thank you for helping me.

[Alan]

#2 is the natural choice.