I have two Baby Bjorn travel cribs for my baby twins and a Phil & Ted travel crib for my older child. Which one is better for air travel? Which one for car travel? There is a difference.
The BabyBjorn travel crib can't be beat for use at home and for car travel, as it can be set up and disassembled in about 30 seconds. We use American Baby Company 100% Cotton Value Jersey Knit Porta-Crib Sheet, Celery and they fit the mattress perfectly, at a fraction of the price of the Baby Bjorn crib sheet. My son sleeps in the travel crib almost every night and seems comfortable, as the mattress is fairly thick and has no bars underneath like a pack n play would. However, at 31", I think he'll outgrow it in a few months as there is not a lot more room lengthwise (the mattress is 24" x " 41").
The material of the crib is also worth noting. It's soft and cottony but over time, it will probably show stains as my babies tend to suck on everything they can. They're not standing up yet.
The Baby Bjorn travelcrib is also lot larger folded up than the Phil & Ted's. I wouldn't use it for air travel if you want to minimize the amount of luggage - it's bigger than a carry-on and may have to be checked. I doubt the fine zippered bag it comes in will hold up to baggage handling. It's also way too expensive - it costs almost as much as my son's Bonavita crib!
PHIL & TED'S
The phil&teds Traveller Crib, Black on the other hand is a great travel crib for air travel as it folds up very small, is super lightweight, and fits into any suitcase or duffle - I think you could fit two in a without any problems in terms of size or weight. However, it does take about 15 minutes to set up and to disassemble and fit into the small bag it comes in. So plan ahead, practice at home, have your child sleep in it a night or two so they get used to it if possible, and bring along the manual, just in case. Set it up as soon as you get to your destination - you don't want to do this later on with a tired crying child.
The self-inflating mattress on the P&T is long and narrow, similar to those used for camping. We put the mattress inside and used regular crib sheets on it and tucked them well underneath (the newest model has a vinyl sleeve to put the mattress into). It will probably work for kids up to age 3, as any older, they may not like being confined in a smallish space. My two-year old child slept well in it on long trips and it still looks new after much use, with a material that is easy to clean.
Although harder to set up and dismantle, I found the Phil & Ted to be great quality, super compact and much less expensive than the Baby Bjorn travel crib. It's also likely that I'll be using it longer than the BB, as it's more compact and can be used outdoors as well.
In a nutshell, both are good but with some disadvantages - the Phil & Ted crib is better for air travel and indoor/outdoor use, while the BabyBjorn one is better for home and car travel. Regardless of which you go with, it may be a good idea to put your kids in their stroller or bouncy seat while you assemble either one of these (like the Go-Pod Portable Activity Seat in Pistachio by Kidco. You don't want little fingers in the way.
Finally, once your kids outgrow these travel cribs, consider getting the excellent AeroBed Sleep Tight Inflatable Bed for Kids. It works well for kids three and over, with built in side and end rails, sheets, detachable electric pump and storage bag with shoulder strap. It's very comfortable, easy to clean, can be used at home for sleep-overs and great for trips.