If you are flying with a car seat, skip the Gogokidz Travelmate. It's basically an overpriced plastic luggage cart. You can buy a metal-based cart (much more sturdy) and it'll do the same thing, usually at half the cost. Use an extra bungee to secure it.
I'm a big believer in less-is-more when it comes to travel products. I think parents are duped into buying far more than they need in all categories, travel included. The GogoKidz is a good example. Try to prioritize products that can be used again for non-travel uses.