You misunderstood my point. I was NOT speaking of rear-facing toddler seats, but INFANT seats, which are and always have been for rear-facing use only. I remember quite well when the industry decided to raise the weight limits on them, and the stated reason was because there was a significant rise in the number of children *under* 6 mos. old who weighed more than 30 lbs. It was definitely about the weight of the youngest children, not the longevity of seat use.
OK... but the
industry, as a whole, has not raised weight limits on infant seats. Only
one infant seat currently has a 30lb r/fing weight limit and that is the Graco SS1 (that is, here in the U.S. anyway). The Chicco Keyfit is also supposed to be reintroduced on the market this year with a 30lb limit, but the ones currently being sold are still 22lbs. The shells are also a little bigger, so they can accomodate a taller child as well. Kids are more likely to last a year in an SS1 because the shell is longer (outgrown by height when the head is 1" from the top of the shell). Every other infant seat on the market currently still has a 22lb limit, so I guess that is why I missed your point.
Anyway, weight limits on car seats are usually misleading as many kids outgrow seats by height before weight. Unfortunately they don't put that on the box for people to read when they're buying them at the store.
Same thing with strollers really - even if the weight limit is high, if you have a very tall child, they might still be scrunched up in a stroller that doesn't offere enough head room under the hood, or enough leg room from seat to footrest. We have a Kidco LS2000 stroller and ds's feet now can hang past the footrest. The canopy is tall but his ears are almost halfway past the top of the seatback and he's just got a few inches until I'll have to remove the canopy altogether. Of course, it's gotten to the point where the only place we even use the stroller is at WDW so when he totally outgrows it (or it falls apart because dh uses it to tote 80lbs of groceries

(think pop & bottled water here) from the rental car to the room, then we'll probably stop using it altogether or just rent when needed.
Now that I've gone completely off topic.... back to regular programming.
