Great product.Had it for nine months. Bought it because I am unable to breast feed and my baby goes through a lot of bottles. Boiling was very tedious and dangerous. I can fill up the sterilizer with baby on my hip. Could not do that when I boil bottles. Yes there is some brown build up, but just clean the sterilizer after some uses. I got this initially because I was advised to use Dr Brown bottles with the vents. However. Y baby doesn't need them anymore but any bottle that we have fits nicely. Great product. 100% satisfied.