I'd have to agree that in a lot of ways, buying a house together is just as big a commitment, if not more, than getting married. And if you're WTT, having a baby together, to me anyway, is a bigger commitment. The disadvantages though, do include less protection/regulation from the law should things go wrong further down the line and lesser tax benefits... but to be completely honest, if these were the only reason someone chose to get married, maybe they shouldn't have bothered! x