I am 5'7, should I get a Small or XSmall?

Tech Specs:

Material:

[membrane/laminate] DryRide Durashell (2-layer); [lining] taffeta 

Insulation:

[body] 60g ThermaCore; [sleeve] 40g ThermaCore 

Fabric Waterproof Rating:

10,000 mm 

Fabric Breathability Rating:

5000 g/m² 

Hood:

yes 

Fit:

TWC Sig 

Venting:

underarm mesh 

Powder Skirt:

yes 

Pockets:

2 front zippered, 1 chest 

Recommended Use:

snowboarding, stomping double mctwist 12's, standing on the podium 

Manufacturer Warranty:

1 year