Halfway there, his IFR approved GPS suddenly craps out, but his 396 with XM
is doing great, and has plenty of power.

What other IFR approved navigation equipment does he have?

If he has VOR, and there's a VOR approach at the destination, I see no
reason not to continue on and shoot the VOR approach with the IFR
certified VOR equipment on the aircraft, using the handheld GPS for
situational awareness.

Jose
--
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