I bought one for my father to use in his glider (i also bought one for my
self) and we had a devil of a time getting its NMEA output to work to his
EW baraograph, in the end we had to send it back to Garmin in the UK for
them to work on it, seems that its a problem with these that Garmin won;t
publicly acknowledge but will fix if you badger them enough. Seems that
the serial output does not get driven unless it can sense a load on the
cable, and the EW doesn't provide enough load to get the signals to be
driven...(you can plug a PC serial port in and see the output no problem)
they fiddled with my dads system somehow and it works now...

I haven't had mine modified, but I also just bought a Lowrence AirMap 600c
and it seems to have as good a display if not a little better (bigger),
its $100 cheaper and a few more features that can be used by gliders
pilots (like acheived instantaneous glide angles and time to impact
terrain (which it also knows). it seems a little lower build quality but I
think it will work out better...

I may be happier with the Lowrence, but I haven't flow with it yet...

and I don;t know if it works to the EW either.. I'm in California and my
dad is in the Uk where the EW is too :-) ...