So, just to be clear on what you mad scientists have determined
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, Cranberry Extract is just as effective as Rez Block for keeping glass pieces clean while costing about 25% as much for bottles twice as large (or 12.5% as much). That being said, you also recommend neither be left in a glass piece for more that a couple of days or so or risk bacterial or fungal growth.
Next you guys need to work on the deficit...
PS: I am assuming there is no way to get the 1/2 off any more and I am talking at $5 a bottle.
The 25% coupon someone posted did work for me however.