Just finished fitting these to my Phantom, 1 test flight later i am very impressed, they are quieter and position hold and flying is very smooth indeed.
I had already replaced the stock rubbish plastic props with stiff carbon reinforced and carefully balanced ones, these made a big difference and seem to add an extra couple of Minutes air time.
The T-Motors make it even better, next step is to install a Futaba S-Bus RX, i will use the TX for my SkyJib as well. Then do something with the landing gear which does like to tip over on anything other than a glass smooth surface.