each letter/number (is there any option for a keypad, btw?), NO
For the 430 it's only $1,500 but I'm not sure when it will go up. Don't
forget that you may need a different antenna cable, and certainly will
need a different antenna, in addition to the cost of the WAAS upgrade.
This is not included in the $1,500. You may also need separate
annunciators for an additional 800-1,000 if the distance between your
primary flight instruments and the Garmin unit exceeds a certain
distance.

You will lose some functionality, such as display of nexrad data on the main
map page, and in the current software version the ability to calculate winds
aloft. These are supposed to be addressed with future upgrades.
..

From discussions w/ avionics shops, that $1,500 is good for the 530 as
well. -see above.

If you have a 430/530 combo, you will need to update both units to WAAS in
order for them to cross talk flight plans, etc. The upgrade is much more
useful in the 530. The weather download requires a GDL-69, which I recall
was around $4,000, while Stormscope was around $8,000.

Understood on the cost & the yoke space--but, am I reading you correctly,
the display on the 496 is *larger* and/or *more detailed* than the 530??

The 496 does show more stuff like winds aloft, etc compared to the 530, but
the screen is smaller/
didn't know that.... The handheld backup aspect of the 496 already has me
leaning that way--but this would cinch the deal, particularly given the
cost

I fly a plane with dual electrical systems and separate busses, so do not
carry a backup GPS, even though I have one that sits in a drawer. A yoke
mount can be great, but tends to block the view of the panel.

- Finally, a pure newbie operating question: the green bearing pointer
in the default nav view--is that always a GPS bearing pointer toward the
next waypoint, or will it act as a VOR bearing pointer? Waypoint, which
of course can be a VOR

Not sure about the 530 as I have a 430 but I believe if you set it to OBS
mode with a VOR as the reference waypoint it will act like the bearing
pointer. If you have an HSI you can dial in the bearing to the VOR in OBS
mode, to intercept an airway, for example.

I experimented, the bearing pointer always points to the next GPS
waypoint--doesn't matter in OBS mode or not.
Again, you can dial in a bearing if you have some sort of heading/nav
function. Try turning the OBS on your VOR head to the right radial, and
see if the magenta line changes on the map page

With a 530, the WAAS/nexrad?stormscope is really worth the improved
situational awareness. With a single 430, the smaller screen with lower
resolution may not justify the added cost.

The combination of 530/430 is great. Depending on the situation you can get
a lot of info- Taking off I might use the 530 in NAV, with the 430 in
Traffic mode, enroute it would be NAV/NEXRAD, terminal area NAV/TRAFFIC, and
landing it would be NAV/TERRAIN. Both units are independent, with separate
nav heads on the panel. It has been a great asset to flying those long cross
countries, in addition to listening to XM satellite radio along the way.