What he said, squared. About the only thing I can think of that you can
do
with a DME that you can't with a terminal-certified GPS is use it to fly
an
ILS-DME (because you don't have the location of the ILS DME ground station
in the GPS database). Unless you have some very specific reason to need
DME for one of the very few things GPS can't replace it for, I think it
would be foolish to invest in DME these days.

Roy, you corrected yourself in a later post.
If I understand it correctly
ILS-DME approaches if loaded into the IFR GPS can be flown with the GPS, How
else could the new DA40-180 and Garmin G1000 do it? Waypoints loaded into
the ILS course provide the "distance to" information needed for an ILS-DME
approach.

Review AC90-94 and the AIM on IFR GPS in lieu of DME

As a side note, our local FBO got a "new" BE33 on the lease back rental
line, DME is broke.. the owner (Private Pilot) did not know what it was..
and did not know what "DME" was. The local radio shop told him he'd spend as
much trying to figure out what was wrong as to replace it. The owner decided
not to repair it, just placard it INOP. So, he just took away all of his IFR
rentals.

BT