This filter system was recommended to me, but we still spent a few months researching different systems before deciding on this one with the 4 cartridges and I'm so glad we did! I dealt with a lot of health challenges for many years, some of which greatly affected my gut, to the point that I could only drink certain kinds of bottled spring water. We had an RO system with a remineralization filter added and for whatever reason, the water just didn't sit well with me. We also really wanted a system that was tank-less so we could save water. This system checked all of our boxes and to top it off, the water not only tastes better than all the expensive spring water I've been drinking, but I actually crave it! It feels so good to my gut! No more heavy (and expensive) glass bottles of spring water! I am so relieved and so happy and so thankful to Art for answering all of our questions (we called several times with more questions!). I would highly recommend this system and this company!