pregnant with twins, due May 10th- we have a snugride (reg. one) that will expire Dec. 2010 - we definately need to get one more- my question is should we get two new ones? will my old snugride last? My first child who was 10 lbs 6 oz at birth was out of the snugride by 6months - but I know twins tend to be smaller so I am wondering if they will be in them longer ? also should we cosider upgardingto the snugride 32? i have read these are heavier, wondering if any of you multiple Mom have experience? thanks