I'm ready to buy a cross bike and I've been looking at Giant and Cannondale... My husband is telling me that I should get a ten speed because that's what our other bikes are, so it will make swapping parts much easier. But, it seems that only the really high-end cross bikes are 10-speed. The more affordable versions are 9-speed.

Is there any other benefit to spending the extra money to get a 10-speed?

Thanks for your help!