Love the quality of Velocio's product. This is my 2nd jersey from them. Per their size chart I am square in the middle of the Small range (5'9 at 155 pounds), but when standing the jersey is snug in the armpits (a bit uncomfortable).
I was going to exchange/return, but remembered the 30-day guarantee, so decided to use it on an hour long ride to see how it felt while riding.
The fit was perfect while riding and the jersey did not bother me at all...in fact, barely noticed it was on!
Ultimately, I decided to keep the jersey, since 99% of the time I have it on I will be riding and not just standing around, lol.