I got this performance knit fabric in two colors to make tops for working out. I've used the same pattern at least 10 times, including with similar fabric from Core Fabrics (the daisy performance knit). I cut and sewed the first colorway up and couldn't even get the top over my head! I was shocked so I double checked the description on the website... the pattern requires at least 50% stretch and this fabric is listed at 60% stretch on the crossgrain and 75% on the grainline. There's no way -- I checked the stretch myself and couldn't really get it to stretch beyond 40% on the crossgrain. Luckily I hadn't cut in to both fabrics yet so I was able to modify my pattern for the second colorway -- I had to add several inches to get it to fit comfortably. Super bummed about my too-small top but the modified one is getting plenty of wear.
I will add that I don't think it's perfectly opaque -- the white designs on the royal blue & white colorway are pretty see through when wet so for swimming and sweating, be aware.
Anyway these designs are so cute and the fabric is high quality, but I learned my lesson to verify the stretch when my pattern depends on that!