I think, SB, that your GPS had a much better database than miy KLN94. I have overlays in mine but they are often only partial representations. Hence, I often fly navaid approaches using a DCT to the approach fix and then fly the OBS mode. It works very well... obviously one has to think where one is at any time.
If/when PRNAV (which will never be supported by the KLN94) becomes mandatory in any significant way, I will rip out the KLN94, plus one of my KX155A radios, and put in a GNS530W in there.