Best option for travel for 4 year old

First, this forum has been so helpful to me just reading other posts so thanks to all who post here. I am trying to decide what to purchase for an upcoming trip to Maui and wanted some input and advice.

We'll be flying about 5.5 hrs, then renting a car and doing moderate driving for 1 week (airport to hotel and back, a few day trips or drives to restaurants). This would be for our son who will be 4 years old; he is about 43-44 in. tall now (the trip is in a few months). He uses an Orbit Toddler car seat (FF) in our main car and Britax Frontier 85 in our secondary car. He has a younger brother who just turned 2 and is 36 in. tall, who is in an Orbit Toddler car seat (RF, probably need to switch to FF very soon) as well. We are trying to avoid bringing 2 of these big, heavy car seats and think the 4 year old will do better in the airplane seat without his car seat. We will bring one of our regular car seats for the 2 year old, which he will use both on the plane and in the rental car (leaning toward the Orbit since it is familiar to him, but if there are good reasons to bring the Britax instead I'm happy to hear them). So for our 4 year old, we are deciding between the following options, in order of what we are leaning towards, but are open to any alternative suggestions as well:

1. Safety 1st Go Hybrid that we could carry on in the travel bag it comes with.
2. Ride Safely Travel Vest
3. Bubble Bum booster (or some other backless booster)

Any suggestions as to these or other choices would be greatly appreciated! I am particularly interested in how each of these compare safety-wise. Note that we would not be using any of these as our regular seat at home, we would be sticking with the Orbit and Britax for that. But we would probably have it become our regular travel seat (1-2 trips per year). Also, our son has gotten car sick in the past, so the 1st and 3rd options have the advantage that he'd be more likely to be able to see out the window.

Thanks!

How heavy is your older son? Most kids don't fit on the plane's seat with the lap belt until around 40 pounds. If he's over that you're fine not taking a seat on board in that regard. If he's not you might want to bring a seat.

I wouldn't bring a BubbleBum. I don't think this would be the best time for booster training, he's quite young, and if you're doing day trips I could see him falling asleep and slumping over.

The RSTV is definitely an option if it'll fit him well.

The Safety 1st Go has variable harness heights depending on the shape and height of the backseat and where the tether sits. He may be getting too tall, depending on his torso height already. The Go is usually 17/18" tops. That's about a size six shirt, maybe seven.

So of those, I'd go with the RSTV.

But that doesn't help with the car sickness.

Would you consider an Evenflo Maestro (if he's under 50 pounds and will be when you travel) and use it on the plane?

Wendy

I agree with Wendy, I would suggest the Maestro for your 4 yo and actually if your budget permits it I would buy a Sureride or a Scenera or for your 2 yo. I have traveled with the Orbit Baby Toddler and it was not easy! That thing is heavy and not easy to handle... It is feasible though just not the easiest thing to haul around in the airport and on the plane. If you decide to take the Orbit Baby, I would encourage you to take something like [ame="http://www.amazon.com/Traveling-Toddler-Seat-Travel-Accessory/dp/B000JHN3AS/ref=sr_1_1?s=baby-products&ie=UTF8&qid=1362932766&sr=1-1&keywords=traveling+toddler+car+seat+travel+accessory"]this[/ame] or something similar, it will make your travel a lot easier! Also, the seat does not fit through the X-Ray machine so you may save some time by not even trying and let TSA use a wand or do a manual search, whatever they want to do in that case... Also know where the FAA Approved sticker is so it will save you time at the gate if they want to check it

I would definitely NOT take the FR85, it is way too cumbersome to travel with!

Good luck

Mag