For me, after three buzzing 151 (which I really wish I'd recorded all the serial numbers to see if there was a correlation), I'm still in limbo, also. Until my 141 comes in I won't know if I've finally eluded the buzz.
I can say definitively that it still drives me crazy on my 151 (which will not be returned until it's swapped for the 141 I'm waiting for). I cringe everytime I turn it on and the room is still silent before the audio system catches up and all I can hear is the refrigerator/chainsaw/fluorescent light buzz of the set. I'm really praying the 141 is buzz free or I might just lose my mind entirely.
I've made it clear before, however, that I wouldn't even consider dealing/putting up with the buzz issue if everything else about the set wasn't so spectacular.