Reddit reviews Thirsties Duo Fab Fitted Snap Cloth Diapers, Mango, Size Two (18-40 lbs)

To be honest the insides of the diaper haven't changed all that much. The real difference is in the outside cover.

There are four main types of diaper insides

1. what you linked, the flat diaper or nappy. A simple square of fabric that is folded in various origami-esque folds around the baby and either pinned or snappi-ed in place then covered with a waterproof wrap or cover. Flats are one size fits all and very economical. If you can fold a decent paper airplane, you can fold a flat. I love my flats for the newborn stage as they are AMAZING at catching all that poo but now by the time I've gotten my flat ready my my toddler has gotten up, walked away and peed on the floor. At this stage they really need to be folded in advance (while baby is sleeping so he doesn't "help" you with them)
   
   
2. the Prefold diaper. As the name suggests these are basically large flat diapers that have been prefolded by the manufacturer. They are extremely absorbent and much easier to use than a flat. here's a great article going into more detail on prefolds
   
   
3. the Fitted diaper. This style of diaper removes all need to fold and pin diapers, and so is super convenient for wiggly little babies that like to dance during diaper changes. The elastics around the legs and across the back help this style of diaper to easily contain the most explosive of poos. For older babies there are Several. Different. brands. Available that are perfect for overnight use. the main disadvantage of fitteds is the price, on the cheap end they are about $10 each but can run for as much as $30 a diaper
   
   4)The Rectangular diaper insert. Simply lay these inserts inside a cover or stuff inside a pocket diaper. Super convenient but sadly not as absorbent as a trifolded prefold diaper or as great at containment as a flat. These are best for older children with solid-er poos, it is often necessary to double up thinner inserts to provide adequate absorption for heavy wetters. Great budget option for moms on the go who need something that takes literally three seconds to put on.
   
   
   
   
   There are also four main styles for the outside of the diaper.
   
   
   
   
   
4. the simple cover, something like the Thirsties duo wrap or the Bummis super whisper wrap. These are simple water resistant exteriors that are placed over top of the absorbent diaper insert. They work great in combination with flats, prefolds, fitteds and inserts and are easily the most versatile of the diaper cover options. Most covers are made from a water resistant fabric called PUL, but it is also possible to get them in naturally water resistant fabrics like Wool
   
   
5. The Pocket diaper, this is what most people think of when they say modern cloth diaper. there are expensive brands like Bumgenius, Apple Cheeks, blueberry and AMP
   And discount brands Imagine Baby, Happy flute and Alva Baby. Stuff the pocket with a rectangular insert, a prefold or a flat diaper and then it is as simple as snapping the diaper on the baby. Like flats these diapers require a bit of prep, after washing it is necessary to take a few minutes to stuff the diapers. But once they are stuffed they become an easy diaper for daycares, cloth resistant relatives and babies that wont stay still long enough for an old school diaper.
   
   
   
6. All in Two diapers are really similar to pocket diapers but instead of stuffing a small pocket you just snap an insert onto the shell. Popular brands include grovia hybrids, best bottoms and Soft bums. These diapers are extremely convenient however its hard to customize absorbency and the proprietary systems can be quite expensive.
   
   
7. All in One diapers. These diapers have it all together in one package, no folding, stuffing or snapping required. Just take the diaper off the line and put it on the baby. Mainstream brands and discount brands are available. the only downsides with AIOs is that they are expensive, can be hard to wash and take a very long time to dry.
   
   
   
   

I got 4 of these and two used covers from a local mom. I stuff them with these hemp inserts, but I've also used inserts that aren't as absorbent, and once I forgot to put an insert in at all... but still no leaks.