Rude Medela customer service (vent)

I called Medela customer service today because the other morning when I was pumping I noticed that my nip was bleeding a little. After a closer look I saw that the inside rim of my breast shields were cracked in several places. I looked at my other set and they were starting to crack too. The woman that I talked to was very rude. First she tried to convice me that someone must have stepped on them. When I assured her this wasn't true she insisted that is must be how I washing them. I told her we don't even have a dishwasher. Then she asked me about sterilizing them. When I told her that I boiled my first set she wanted to know HOW I boiled them. My answer was that I did it exactly how it said to in the instrucions that came with my PISA. When I told her that I never boiled my extra set she said that it was because I was using a microwave sterilizer and that their stuff isn't tested with other company's sterilizers. I understand her point, but her tone the entire phone call was very accusatory and she even actually laughed at me at one point. All I was asking for was a reason my parts were cracking. She agreed to send me a replacement set but acted like she was doing me a big favor even though the parts have a 3 mo warranty and I have only been using my pump since DD was 3 weeks old so it has been less than 3 months. I sure hope nothing else goes wrong with my pump!