TL;DR: Great budget sports bra that does its job wellBackground:I have recently began training for a marathon. As a result of all of my running, I've lost some weight. (Yay!) However, there was an unintended casualty of the weight loss: my boobs. ***a moment of silence for all boobs lost during our fitness journeys*** I definitely lost some size and needed some new sports bras. Being a life-long Angel, I headed to Victoria's Secret to get sized and pick out some new ones. Well, I am now a 34D and found a few in store that I liked, but I just could not stomach the price. I left empty-handed and scouted here on Amazon. I came across these and liked the styling and the price. I ordered a large based on the sizing guide.Initial Review:My initial thoughts were that the fabric at the sides of the bra (the part that goes under your arm) is a bit thin. There is very little padding in the cups, at least compared to my (now former) VS Incredible and Ultimate bras. I was a bit concerned that with the fabric and padding being so thin, I wouldn't get the support I needed during my runs. The cups were a tiny bit larger than I would have liked. There was a little room at the top of the cup when I put it on. The band was comfortable, although I am on the first set of hooks, so if I get any smaller in circumference, I'll need to go down a size. The thick, adjustable straps felt very sturdy without digging into my shoulders. To be honest, I felt probably could have gone to a medium as I like my sports bras to be snug, almost to the point of squeezing. Overall, I had my concerns about the thin fabric and padding and it's ability to support me, but I was ready to run and give this a shot.The Test:I used the bra during an 8 mile steady-pace run. To my slight surprise, the bra performed well, just as well as my VS bras. The bra moved with my movements; never once did it pinch or chafe. No obvious bouncing. (I mean, there's always going to be a little movement, but I didn't feel like they were bouncing like two energetic monkeys bouncing in a cage.) I felt comfortable and supported throughout my entire run. Granted it was a cool evening, but I did feel like the bra wicked away what little sweat I had. The "mesh"/ventilated fabric kept me cool even to the last mile. I was not sore after my run nor were any "sensitive areas" irritated. ;)Final Verdict:While this bra lacks the "sexiness" of the VS sports bras, it performs just as well as they do. It is a practical, functional sports bra that an endurance runner can rely on mile after mile. As a 34D, I would probably order a medium, but that's due to personal preference of snugness of the band and cups; the large was comfortable and supportive for my size. I will definitely be ordering a few more in different colors. I am very happy with this bra.Update (3/16/18): I found and purchased a medium size of these at Burlington Coat Factory (on sale too!), and it had more of the "squeeze" that I am used to. The cups were more of an appropriate size as well (no extra room at the top). However, I am on the final (inner-most) hooks, so if I gain any circumference, it would be uncomfortable. I wore the medium during a 5 mile club run, and it performed just as well as the large as described above. It was a bit tighter, but still no chafing or pinching. So, in regards to size, it seems like a 34D could either fit in a medium or a large, just depending on how "packed in" a person would like to feel.