I got the GNS-430W back and installed
Garmin promised a turn around time of only a couple days and amazingly enough they were right. They had to ship it to the company I bought it from (Pacific Coast Avionics in my case) and then PCA shipped it onward to me. Total time out of the airplane was 10 days.
Total cost: Upgrade: $1500
Shipping to: $95 (2 days, Fedex fully insured)
Return: $30
TNC adaptor: $13
The instructions from Garmin say that the GPS antenna cable needs to be RG-400 with a maximum length of 13'. The connection on the new antenna is TNC rather than BNC thus the need for the adaptor (or a new TNC end for your antenna cable).
The unit comes back with all of the default settings (8.33KHz radio spacing, time set to UTC, all the ARINC and serial outputs off etc.)
You get a new datacard with the latest Jepp data. You also get a new terrain card (but that may only be because my unit had the terrain update in it).
I have only flown the airplane for an hour since the upgrade but so far I am very impressed. The update rate on the map is so much nicer than before. Also distances are displayed to the hundredths of a mile (9.07 miles) and it is very cool to see the distance data being updated continuously.
Map scrolling which used to cause a few second delay when you move the cursor off screen is now instantaneous.
I have yet to try an LPV approach (I have to find one in my area first). I am not sure whether Jepp is going to charge me more for my updates with the extra approaches (let's hope not).
I also sent my TruTrak Digiflight IIVSG back to them while the Garmin was in the shop. I had version 2.18 of the firmware in the autopilot and they updated it to 2.22. They told me that they had made several changes to improve altitude holding (though I thought it was rock solid before). The only difference I could find was the display has changed from black words on a grayish background to yellow words on a darker gray background.
Bruce
RV-8
N297NW