I think it really depends on the couple. I know of a couple who dated for over a decade, got married, and were divorced in two years; and of a different couple who went on a few dates, and were married within 3 months (about 40 years later, after his wife's funeral, the husband said they had had the best marriage he had ever seen anywhere.) To be fair, the first couple were not Christians; the second were both extremely devout, prayerful Christians whom God very clearly directed towards each other. A very cool story, actually.)
Both couples were exceptional opposites.