Love, love, love this product for travelling!

We bought this product for travelling,after doing a lot of research once our little one outgrew her Kangaroo Pouch and doing one awkward trip with stroller, carseat, diaper bag etc.
Our two big decisions were based around having a kickstand or not, and top loading vs side loading.
We eventually decided on the 2.1 which has no kickstand thereby making it easy to take on board the aircraft rather than gate check it and risk damage by the airline. It has a nice detachable bag that you can keep diapers, toys, purse etc in while putting the carrier in the overhead locker. It even fits nicely on the smaller regional jets.
The fact that it is toploading is a personal preference and while I can't argue it would be easier to open it up from the side, we have had very little difficulty just popping our ten month old in it from top. I would definitely recommend trying one in the store before you buy.

We ended up buying separately the sun/rain hood and it has been nice to go outdoors with her while on vacation and not worry the whole time that she is frying in the sun. I would however beg Kelty to put the detachable front pad(rests between baby and the frame of backpack)that they have on the 3.0 on this carrier. Our daughter loves to chomp down on this part of the carrier and it would have been really nice to have been able to put it through the washing machine instead of just spraying sanitizer.

Other than that, it has been a huge help when I travel alone(and I do that alot)-it does take a lot of the stress out of the equation. I would thoroughly recommend it to all women as being comfortable, having a nice big waist strap to go around even the biggest stomach, and being really easy to manipulate the baby in and out by yourself. One tip to end with, stand on the waist strap as you lift the baby out of the carrier - this makes it easy to separate the two quickly.