Rockin' Fitness Wear (Cleo the Hurricane/Georgia Moon)

Hi everyone, I'm just wondering if anyone has bought any of Cleo The Hurricane's "Rockin' Fitness Wear" range? I want to try it, but am not sure of the sizing.  At a recent workshop with her, I bought her "Rock n Pole" T shirt in a "large", and it's none too large on me....it's not over-tight, but I wouldn't want to go down a size.  For reference, I have a narrow back but am boobalicious.  The shirt doesn't actually *pull* across the boobs, and I like the way it fits, but now I'm wondering about the Rockin' Fitness Wear range, and whether the sizing is similar in that?