Personally, I don't think that any differences are 'canceled out'... I believe the differences will always be there, and MAY (but not necessarily) cause problems. It's like two people, one grew up rich, the other poor...or one came from a different religion, a different culture, a different country, whatever. We're all different as Christians. Just because we're saved doesn't make us all the exact same, and thank God for that one! The differences can be an issue, but they can also be 'the good stuff' as well.
You have been shaped and molded by every single event that has happened in your life, the overwhelming majority of which are completely different events than any other human will experience. It is impossible to let that all go. We've all got good strengths and we've all got weak areas that we need God's help in.
What I'm saying is...EVERY single relationship has different people with different backgrounds, circumstances, ideals, morals, etc. Will it work? Absolutely maybe. That's the best answer I can give.