Just get your shutter speed above about 1/1000 and get lucky enough to freeze the beats at the top or bottom of the stroke (the wing velocity stops there). ISO 1600 is your friend here.
I do not recommend a faster aperture. Hummingbirds are small subjects so you are very close to them. The depth of field at this magnification is already razor thin. My best shots are shot at f6.3 and the entire bird is still not in focus.
Also if you are considering a super-tele, look at the close focus distance/ magnification ratio. You need a very close focus which many high-end teles do not provide.
Phillip