So is the cost actually low? The last time this came up on HN people agreed the costs are standard and the other pharmacies do not charge the high prices on the comparisons.
But are you taking into account how much a month you are paying into that insurance when comparing the two?
If CostPlus is coming close to what you are getting your prescription for with a paid into insurance plan, than I would call that a win for those without insurance.
Might be worth looking at lowering my own insurance coverage to one that might not be that great for prescription, as long as costplus and costco type places come close to after insurance priced meds.