Bad quality taps

A few months ago we replaced our taps in the home with Cobra taps, thinking to rather go with a well known name and quality. At first we did not notice, but as the days went by, the water started tasting funny. At first thinking it might be the municipal water that is the problem. But it just got worse. Then a few days ago we decided to do an experiment. We replaced the outside tap with a ball valve. Immediate difference. So now what happened with the quality and all the money spent?