I purchased these early in my pregnancy because I grew out of my regular clothes very quickly.  Pre-pregnancy I wore a 00, so technically I am just below the sizing threshold for this product.  At 22 weeks, they are just now getting to the point were they mostly fit, but I still have gaps of a few inches here and there where my body doesn't quite reach the bands, especially on the top.  I expect by the third trimester this will no longer be an issue.

What is upsetting is that after three wearings, the seam on the black band began to unravel.  I didn't expect these to become family heirlooms, but I did anticipate being able to use them for the less-than-one-year-period of pregnancy without them falling apart.  Very disappointing.

Update:
At 26 weeks I am still using the bands occasionally and have trouble keeping them in place.  They seem to want to migrate north, and I find this happens more frequently with the black band than the white.  It tends to bunch up just below the bottom on my bra, creating unsightly ripples through my clothing that make it look like I have a righteous case of back fat.  I think I am ready to give up on these bands entirely.