I purchased the 60E550 two week ago and am really liking it. I have a little buzz, but it's only noticeable when there is not sound in the room whatsoever. I'm letting my 100 hours of break in go by before I tweak the settings. I did turn off any DNR settings though. 3D has been good and this from a person who is not a huge fan of it. I watched Flying Swords of Dragon Inn the other day and it was awesome. I did pick up some better 3D glasses, as I wear glasses and the cheapo Samsung ones are not comfortable to me. There is some glare during the day as the bay window is on the east side of the room, but I'm at work during the day anyway.
This set replaced a 46" Samsung LCD that was about 4 years old, only 60 Hz, so it's a big upgrade for me. I wanted to get a 60" ES series LED, but it was out of my price range, the 55" was in the range. I really wanted a 60" and I'm happy with this plasma.
One cool feature I did not know about caused a funny situation. My TV kept bringing up Netflix and I could not figure why, checked my One remote settings, all was good. Finally figured out my daughter was watching Netflix on my iPad and it was prompting her to watch on the TV or the iPad. Very neat feature, didn't even have to configure it.
Overall, happy with this purchase for the price. I put my old 46" in the basement, and sold my old Toshiba 40" LCD that was down there to my sisters family.