The Gogokidz Travelmate is basically just an overpriced luggage cart. You might as well go over to Kmart or wherever and for half the price, get a luggage cart that is a lot sturdier. I did this with several car seats and it worked just as well as a Gogo. Plus, it's a useful contraption you'll be glad to have (if you don't already) next time you move furniture, house or need to haul big items to the car...

Use an extra bungee to secure it. Sometimes parents manage with the LATCH straps. Works just as well!

Mine has a telescoping handle (nice, not a deal-breaker) and a metal, not plastic (like the Gogo) base. That's highly recommended. If you're tall, make sure it's not too short.

As far as the other contraption is concerned, I'd be worried about that amount of weight on the handles. If it breaks, you possibly have an injured kid and have to drag him/her and a handleless bag through the airport. Sounds grim...

I'm also not a big fan of bringing rolly bags on board as carry-on's. There just wasn't enough space to store them all! We really dreaded seeing them and we often grabbed them first to gate-check. Keep this in mind if you have a laptop or similar non-checkable item.