The Militia Guardian, which was released in July 2000, was the
same basic shape as the earlier (pre-1998) Guardian Angel. The
main difference is the chevron shaped cutouts in the handle,
where the Guardian Angel had rubber inserts. The other major
difference is the larger button that is flush with the surface of
the handle. This is the first instance of Mr. Dalton using this
type of button, which was used in several later models, including
the Militia Recon, SOB I, SOB II, Slim SEAL, and Wharncliffe.
"MILITIA GUARDIAN" was engraved into the handle. Minor
differences include a more closed back on the Militia Guardian,
and differences in the number of notches on the upper and lower
edges of the handle. Here is a picture of a 2-tone Militia
Guardian:

I have seen only black handled versions with both full beadblast
and two-tone blades in this model, but don't recall seeing any
with PROTO markings, serrations, or any other variations or
colors.
Here are the dimensions:
Overall Length: 7 - 3/4"
Blade Length: 3 - 3/16" (angel blade), 3 - 1/8" (SOG
blade)
Blade Thickness: 1/8"
Handle Thickness: 0.490"
The next model, released in August 2000, was the Militia
Recon. This model was very similar to the Militia Guardian, but
had three beveled round holes on each side of the handle instead
of the chevron cutouts. "MILITIA RECON" was engraved
into the handle. I have only seen this model with gray handles.
The first batch of these was a small run with the blade used on
the Guardian Angel. I have heard that only about fifty of these
were made with blades left over from the Militia Guardian. I
don't recall seeing any other variations of the Militia Recon
with this blade. Here's a pic:

The remainder of the Militia Recons were made with this SOG
shaped blade:

I think I may have seen a 2-tone version of this one, but don't
recall seeing any other variations, except that some had U.S.A.
etched on the blade under the logo.