Take a look at all the 1-star reviews for this product. You will find that almost all of them are related to the size 3 version of Swaddlers Sensitive. Unfortunately my experience has proved the same --- the size 3 versions of these diapers are indeed (for whatever reason) different than the size N through 2 of this diaper.
My daughter has been in Swaddlers Sensitive since she was born (started in size newborn). They have been great diapers for her --- rare blowouts, rare diapers rashes, and if she did have a rash it was usually easily remedied by moving up to a larger size.
This all changed when we started her on Size 3 of the sensitive swaddlers. First, I found I was changing her more frequently (or at least checking her diaper more frequently) because of a horrible chemical smell coming from her diaper region. I thought it was just me --- but reading reviews here confirms that it is the diaper. For some reason, the size 3 versions emit this horrible chemical...