Luggage from Costco is well thought of by some frequent travelers, seems to hold up well for the price. Also check sales at Kohl's as well as TJ Maxx. Not sure a set is really the way to go, they often include pieces that you really don't need. Rarely do I see people at the airports with perfectly matching sets of luggage so consider mix and match to get what you want at the price you're willing to pay. As others have mentioned, make sure you don't get anything too large-IMO 24" is max I'd go. Over that and it can either be too large to fit easily in a car or prone to going over the 50 lb weight limit if flying (not to mention challenging to maneuver while keeping track of kids, carry ons, etc.) The most durable material is probably ballistic, but other nylons will also hold up (higher denier count is better than lower in general). For me finding the perfect carry on bag is more difficult than deciding on luggage..... Good luck!