My rather sad observation is that ALL pilot shops are so full of old junk, almost completely unchanged for years (with the exception of ATPL study material and leather jacket fashion changes) that a new GPS is the only thing worth looking at!
As an electronics engineer of many years' experience I remain amazed at how backward even the latest GPS units are. Poor screen resolution, poor data interfaces, poor rendition of the database.
One day, somebody will do what is becoming obvious to anyone who has played with digital mapping (rip off a few gigs of public domain 3D terrain data such as that used by NASA World Wind or Google Earth) and put it inside a modern 640x480 lightweight product, giving virtual VFR.
The problem is that due to Garmin's firm position in the generously margined retail channel, the only way to market it will be as a PDA product for something like an HP4700.