R Avery wrote:

I have conducted my own speed tests using
Application.Worksheetfunction.Index, and it is slower than a custom
function by a factor of 1.4 to 30, depending on the size of the array.

Does the Index function offer any benefits over what my ArraySlice
function (other than the fact that I would need to add code to make it
handle Rows as well)?

Also, are there any builtin functions that can return a subset of
columns from the original array? For example, if I want to get a
variant array containing only columns 2, 3 and 5.

You might want to take a look at the freely downloadable file at
http://home.pacbell.net/beban, although speed of execution is not their
forte. It includes RowVector, ColumnVector, SubArray, and
ReplaceSubArray procedures, along with some others that might give you
some ideas.

Alan Beban