Sized vs One-Size Diapers
When some parents first lay eyes on a one-size diaper, the whole thing and look overwhelming. The 3x3 grid of snaps on the front, plus the row of snaps around the waist, can make for upwards of 25 snaps on the front.
How on earth would a parent be able to figure all that out during a bleary-eyed, middle of the night diaper change? Thankfully, one-size-fits-all products aren't that hard to figure out- but they do have pros and cons when compared to comparable sized products.
When we talk about the "fit" of a cloth diaper, we're looking for the way the diaper hugs the legs and waist. Is it too tight and leave red marks? Does it gap, allowing poo to escape? A poorly fitting diaper is frustrating (and messy!). Different brands of diapers fit in different ways, but, generally, sized diapers will fit better at any particular size, since they're made for the baby of that particular size. This is more obviously true at very small and very large sizes. Although one-size products advertise they fit from 8 to 35 pounds, often a sized cover is needed until the baby reaches 10 or 12 pounds. Some toddlers will outgrow the rise of a one-size diaper before 35 pounds, too- but many potty train before this point.
As far as sized and one-size covers go, one isn't really more trim than another- it's what's inside the covers that make them bulky! One size inserts tend to be bulkier on smaller babies (since they're designed to work for toddlers, too). Same goes for one-sized all-in-ones- the absorbent layer is overkill for a younger baby, so there's more "fluff" than necessary. Sized all-in-ones, like the bumGenius newborn AIO, are much trimmer, since they have just enough absorbency for the child's size. Using the appropriate size prefold or hemp insert in a cover affects the trimness as well.
Ease of Use
The one-size covers, while intimidating with all the snaps on the front, really aren't terribly hard to use. Once the rise is set correctly for the baby, no changes need to be made to the snaps until the baby's ready to move to the next size. Sized products are ready to go- no settings necessary!
The length of time these diapers will be used will affect their lifespan, and durability over multiple children. A one-size diaper will be used on one child for around two and a half years- birth to potty training. After one child, the diaper may be worn out. A sized cover will be used for a much shorter span of time, so will last through more children or be in better shape to resell when it is no longer needed.
One-size and sized products tend to fall in the same price ranges, so, for each diaper or cover, there's not a huge difference. The economic difference comes when looking at how many diapers you'll have to buy over the child's birth-to-potty-training years. For a one-size product, you'll theoretically only need one cover, while you'll need 2-4 sized covers for the same time period. (Some parents choose to skip the Newborn size if they have a large newborn, and some children potty train before hitting the Large size.) When taking into account multiple children, though, the costs tend to be about the same.
The decision on whether to go with one-size or sized diapers really comes down to preference. If you truly want to cloth diaper from birth, we do recommend getting newborn-sized covers or all-in-ones, since one-size diapers don't fit skinny newborn legs particularly well. After the newborn stage, consider the above pros and cons, and pick what works best for your family!