Short answer: no. I think the idea is out of romantic novels and movies.
Longer answer (and you knew it was coming!
): I think there are any number of people that we could be happy with in a relationship. I think compatitibility and committment are much more important than that "instant connection". Attraction is instant, real love takes a boatload of work.
I also don't believe in finding one's "better half" or the someone to "complete" you, or fill up some emptiness inside. I believe instead you better well be complete and filled on your own before you even try to find someone. To search around for completion or someone to fill in the blanks is asking for an unhealthy relationship.