u/Any_Discussion_9832

So I found a stockist with an Auralite short sleeve at a really good price (better than ordering from the official website) but they only have size S and I usually wear XS on most clothing. Any insight on how the Auralite shirts fit? Any considerable differences between XS and S sizes?

Edit: guess I was misled by an instagram post but thank you all for your input!

This may have already been asked before, but am I understanding correctly that there will be no water cups along the course and I have to bring either a bottle or stop at refill stations?