I own 2 Britax Frontiers in Pink, and the Graco Nautilus in pink as well. As a Mother who owns both models, I will tell you the major differences between these two seats from my point of view.
#1 Frontier is more expensive (which is why I got the Nautilus for my spare)
#2 Frontier is SO much easier to adjust the shoulder height strap. With a simple squeeze of a lever, the straps go up. The Graco needs to be rethreaded. This is BIG pain when you have another child who wants to use the seat. With the Frontier, it is no biggie to pull the lever.
#3 Frontier seat material is prone to wear where the child's bottom and legs rub on the seat. It also shows WAY more stains and soaks up spills quicker than the Graco.
#4 Frontier has 3 crotch strap adjustments for easy fitting. The Graco only has 2 which makes the older kids sit on the strap. This can get uncomfortable. My oldest DD takes the pad off of the crotch strap on the Frontier (she says it makes the seat look like a... Read more

The crotch strap.

This seat looked ideal in every way. I liked it right out of the box, and when I put it together. It was exactly what I was looking for.

Then, I sat our average-sized 3 1/2 year old in it, boxed it up and sent it back, very disappointed.

The crotch strap, in the closest position, was beneath the back of my son's crotch. In the farther (and only other) position, it was even with, and slightly pressing against, the front of my son's crotch. In other words, no room to grow whatsoever. There is no way possible that this seat would allow my son to sit comfortably in a five-point harness all the way up to 65 pounds. At that point, the strap would be well beneath his crotch and be uncomfortable and dangerous. No way... and I really wanted it to. If there was one additional slot for the strap, an inch or so farther out, this seat would be PERFECT, in my opinion.

So, I gave this seat a 3 out of 5. For a younger child, or... Read more

So I did a LOT of reseach before buying this, read multiple message boards, then to the store to look at them, etc. This replaced a britax that was passed down to DD #2 for my rather large 4 yo girl(40lbs, 40inches)I want to keep her harnessed for as long as I can. I finally decided to go for it b/c of
1)price (though it really wasn't an object) but I am a big fan of bang for your buck,
2)sturdiness, i was never a fan of graco until i bought this seat. It's got a nice weight, sturdy frame.
3)comfort, memory foam! DD loves it, she sleeps very comfortably in it without slumping over like she used to.
4)size, not gigantic like the regent but large it enough to have a big kid sit in it
I was concerned about its looks but it's much better looking in person.
Finally, who can beat amazon's price!
I highly recommend it, I think it will last my DD until she's prob 7-8 yo (My average sized 8yo nephew fits!)