I agree with Bev on this one. It is a posibility that they could run out of booster seats, and they do charge a hefty fee I believe almost $10 per day to rent one. I also have seen first hand one of these, since my sister rented one in Feb. They are DISGUSTING!! They are never cleaned, so if something gets spilled, soiled, etc, it just stays there. They are also usually pretty old and just don't look good. After seeing that, I'm glad that I always bring our seats. My DS 2 uses his on the plane, so no brainer there, and for DD 5, I check her booster seat. I purchased a car seat bag from Babies R Us for $20. It protects the seat wonderfully, and I just check it with all our other luggage. It's really a breeze to bring.