When calculating a single quantity item in the store using UPS shipping, my shipping calculations work perfect. However, if I add 2 or more quantities, my shipping rates go up but not exactly the same as what UPS is calculating.
 EE 2.5.3 w/ Expresso Store 1.6.2 / IIS 7 / PHP 5.3.6
1X Item Calculation (perfect) UPS $14.66 Store $14.66
2X Items (different) UPS $29.32 Store $17.25