Product review (1 stars): Flow rate - quality control issue
Received the filter and followed directions.  Ran the water for some time - at first it ran dark black ( never had a filter do that) , I assumed it was the charcoal - then after awhile the water starter to become clearer.  The big problem was the flow rate.  It took over two minutes to fill a 6 oz glass.  Even after the air stopped coming out and had a steady flow, it still took over two minutes to fill 6 oz glass.  I even took it out, looked closely at it and then reinserted it and started the process all over.  Still over two minutes.  Replaced it with my old one and the flow rate was just fine.

A quality control issue ?  I'll be returning the filter to Amazon for a full refund unless I hear from the company on a replacement.

Update: Even before I had a chance to install the filter, the company had emailed me to see how I liked their product.  Once I let them know I had a problem the Waterfall Filter Company was extremely helpful in trying to resolve the problem - strictly a flow rate problem - even sent a replacement one; but it also had the same problem.  Both Amazon and Waterfall Filter Company did an excellent job of trying to resolve the problem and then giving a full refund when the second one didn't work.  Would I deal with this company again ? - yes. An excellent company that stands behind their product.  The two I got just didn't work - fit fine, no problem.  Just the flow rate problem.