Use high helix endmills. Plain uncoated high helix (for aluminum) HSS works well, perhaps even best because some coatings may round over the edge to a miniscule degree.
Climb mill and take a fairly decent chip in the finish cut wherever possible. Light finish cuts do not work well.
I think some burr is unavoidable, but a proper procedure makes a very light burr that is easy to remove with a sharp deburring tool.
First you get good, then you get fast. Then grouchiness sets in.
(Note: The opinions expressed in this post are my own and are not necessarily those of CNCzone and its management)