Hello. I am a customer of many of Kent Wang's merchandise. I originally bought a medium polo. The piqué fabric was nice/soft and the MOP buttons were a nice touch as was the spead collar. However, medium was too large. I ordered a second polo in another colour. This time size small. A little stiffer fabric than the previous one unfortunately. Same nice collar and buttons, though. It fit in the shoulders and arms, but it was not as advertised in terms of slim fit. Laying the polo flat, it is a box fit. It does not taper in, and while wearing it billows quite a bit in the waist and lower back. I had measured against two Ralph Lauren Polo polo shirts before ordering. The reason I went with medium originally was both that Kent Wang advertises to size up from your regular size and that Kent Wang advises that his polos are slimmer than Ralph Lauren Polo Custom Fit, which is too tight for me in size small. I find you do not need to size up for Kent Wang Polos and they are instead true to American regular fit sizing. Both my purchases are at the alterationist. To to poster above, measure a well fitting Polo or T-shirt and give custom measurements to Kent Wang. It costs much less than the alterationist's price. Advantages to Kent Wang polos are that they are logo-less, better buttons, better collar, mid-bicep arm length, and an even hem (no extra length on the backside like Ralph Lauren. I will continue to order from Kent Wang, but was unable months ago to find proper fit picks of the polos with sizing mentioned. I realize I could have helped with that issue before sending them off to the alterationist. I am curious also if it is measurably true that Kent Wang small is slimmer than RLP Custom Fit small. Edit: Just to clarify. The polos are definitely slim on top and in the sleeves. Just not below in the belly.