Thumb Score: +24

Woot! [woot.com] has CAP Barbell 20lbs Adjustable Weighted Vest for $19.99.
Shipping is free for Amazon Prime Members (must login with your Amazon account and select a shipping address in order for Woot to apply free shipping) or is otherwise $6 per order.

Price:
$20.01 lower (50% savings) than the reference price of $40
$20.01 lower (50% savings) than the current Amazon price of $40