I had to write my first review ever on Amazon for this product. I received my first one the beginning of Feb and since ordered several more along with recommending this sports bra to any female I know who works out. As a large 34 D or small 34 DD depending on the bra maker I have always had a hard time working out. I resorted to the multiple sports bra technique or the wearing a regular bra under a sports bra to try to get some support while doing cardio. This bra is a GOD SEND. Not only does it actually support your breasts but the fabric breathes so you don't feel like your strapped in to a wet rag. I often would pass on cardio activites due to not being able to be comfortable while working out... this eliminates this excuse for not working out.
I was shocked to put it on and instantly be able to do jumping jacks with out holding on to my chest with one hand. I use these bras for walking, jogging, running, cycling, yoga. step classes, and kayaking.  It is a little difficult to take on and off but it's well worth the extra 15 seconds of struggling to have this kind of support while working out.
IF you have a larger chest and have struggled with support issues in the past I would highly recommend this sports bra. I ordered the 34 D b/c I didn't want to have a sports bra too large and have found the fit snug and comfortable.