Dfyjkt

Norwegian's checked baggage policy mentions that travelers with children and infants may check a car seat or stroller free. They also recommend putting your stroller in a Stokke PramPack to avoid damage.

Since this costs more than a typical Norwegian ticket, if your stroller isn't gigantic and folds to 56 x 46 x 25, a more obvious thing to do is bring it as a carry-on. The hand baggage policy doesn't mention whether a folding stroller will be allowed as a (not extra) carry-on.

Does anybody have experience with this?

If you manage to find a stroller that is small enough than I guess you could argue that it is one of your carry-on bags - but I haven't yet seen one so small! I often travel with one of these big child carriers (with metal frame and extra pocket for stuff - this one in particular), and I always take it with me on the plane. But it does (or almost does) fit in the size.

Normally you can take your stroller all the way through security to the gate and leave it there just before boarding the plane. On many airports (but not all unfortunately) you can also ask to get the stroller at the gate after landing, so you can use it straight away. One member of staff once explained that the strollers left at the gate go to a different hold, so the chances are they will not get damaged. You also avoid all the conveyor belts, which obviously might damaged non-standard sized luggage.

My personal approach is to take a relatively cheap buggy with me, make sure I have the receipt for it somewhere, and check it in at the gate. It happened only once that the buggy got damaged, and it was when we were coming back from 6 week long trip to India - so I was pretty happy to get the reimbursement from the airline :)

Your stroller is bigger than the allowable size for hand baggage in all three dimensions, so why would you expect them to allow you to break the rules?

If you want it in the airport, then gate check it before you board. If your stroller does not lock in folded position, maybe bring a compression strap to cinch it up when folded so it is less apt to be damaged. Just remember to wait for it at the gate when you land, as a gate checked stroller get delivered to the gate area not baggage claim.

If you want to check it and not worry about carrying it through airports AND you are worried about damage, just buy a real cheap duffel bag that it fits into. A much cheaper route than the fancy bag you mentioned.

Since the other answers are nonspecific, I'm going to answer myself by saying what happened on my trip this week.

The truth seems to be "it depends on the airport", so don't count on it.

The first thing is that Norwegian doesn't appear to like gate-checking strollers, which was the point of the question.

From Helsinki to Stockholm, the people at the bag drop wanted us to check it. They give you a plastic bag, which is probably as robust as a cheap duffel bag.

From Stockholm to Helsinki, when we went to the bag drop they said "That's a Yoyo. You should just fold it up and put it in the overhead bin." (It fits comfortably in the bin.)