Greetings,
I teach both the GNS 530 and 480, and have written several books on how
to use them. Even though the enhancements to the 480 have made it
somewhat easier to use and it currently offers precision GPS approach
capability, I still recommend the 530 over the 480.

When the fit hits the shan, the 530 is faster to use, has easier
button-press & knob-twist sequences, and generally seems more
intuitive. When I toss an emergency situation requiring a diversion to
an unplanned alternate to a pilot learning their GPS, those with 530s
are headed towards their new destination minutes faster than those with
CNX80s/480s.

From my latest tour of Garmin, I fully expect to see the 530
WAAS/Precision GPS approach upgrade within the next year. Terrain
information should be out *shortly* (much more shortly than this time
last year).

I have a longer and more detailed comparison between the two units. As
soon as I find it and update it, I'll get it posted to the newsgroup.
Fly SAFE!
Jedi Nein