I use the Giottos Rocket Air Blower.  The only dust bunnies probs I have had were early on with my cameras.  Since then, a good blow with the Rocket once in a while takes care of things.  I might have had an "oil" spot or similar something not long after the camera was purchased but with care in lens changing I have little problems.

Be careful, be very careful to have the camera turned OFF when changing lenses.  I tried "pinhole" camera shots with a tiny, perhaps 1/3mm hole or smaller on a cap placed over the camera body. The tiny hole was open to the air.  So, I got dust bunnies! Amazing how small the dust can and likely is that causes the problems!    With camera off, changing lenses is generally no problem but a blast of air from the fairly strong Rocket is well worth it.

Some folks say use "canned air" and I have not tried it. I fear the freezing effect might be a nasty.  I really do not know.      TomDArt.