Ballscrew/linear bearing lubrication?

Now I've finished collecting all the major parts for my CNC mill
project, I have to start thinking of the finer details before launching
into building the thing. I've got THK HSR linear bearings for all 3
axes, THK 20mm ground ballscrws for the Y and Z axes and a Thomson IBL
16mm ballscrew for the X axis. What lubrication should I be using for
all of these? I had assumed that grease was the standard choice these
days, but I have read opinions that light oil is a better option because
it has less tendency to trap contaminants and cause wear. In the finest
tradition of massive over-engineering, none of these components will be
operated anywhere near their design limits, and I'm hoping to mostly
conceal the moving parts beneath bellows (except for the X-axis
elements, which will be relying on the table itself to shield them.)

Since this is a hobby machine, not an industrial production machine, I'm
probably after the "best" solution rather than the "most practical", but
I'd like to use something that is easy to obtain locally rather than
some exotic concoction which can only be ordered in 50 gallon drums from
Japan.

Any opinions?

Richard