wrote:

I'll wager that the 400/430/500/530 don't have sufficient memory for airways.

How much memory could it possibly take? Let's do a back of the envelope
calcultion. Assumptions:

500 airways in the country
Each airway is 1000 miles long on average
There's a waypoint every 20 miles on average.

So, you've got an average of 50 waypoints per airway times 500 airways,
equals 25,000 data points. The waypoints themselves are already in
memory, you just need references to them, say 4 bytes for a reference.
That's 100 kbytes of memory to store all the airways in the continental
US. Figure a Mbyte to store them for the entire world.

I'm typing this on a laptop with 256 Mbytes of ram. My digital camera
has the same. It's just absurd that memory limits in a $20k box should
prevent you from storing airways.

I'm not saying it's not true. Just that it's absurd :-)