As an owner of a Garmin GNS430 who will most likely upgrade to the WAAS
capability, I downloaded and installed the Garmin GNSxxx WAAS simulator
last night, then "flew" a couple of RNAV/GPS approaches with LPV minimums.

http://www.garmin.com/products/gns430/
(simulator download link on right of page)

A couple of differences I noticed right away is that the WAAS upgrade will
provide a graphical turn line on the moving map for the non-compulsory
waypoints along the approach. Additionally, the GPS will begin flashing a
countdown-to-turn with heading message, followed by a "turn now" message.

As you recall, the current GNS430 software only flashes the new heading
prior to the turn and then stops flashing when the turn is to commence.

Here's a screenshot taken just before the turn with the countdown message
showing:

http://img224.imageshack.us/img224/5...6230104xd2.jpg

I then "flew" a missed approach to a hold. I thought I read in this group
a few weeks ago that the new WAAS upgrade auto-sequences to the missed
approach, but in the simulator it went to "suspend," similar to the current
GNS feature. I was required to hit the OBS to sequence to the first
waypoint along the missed.

The hold was also pretty slick. The GNS430 with WAAS depicted the hold
entry on its moving map, along with another "turn to a heading" message
count-down. At the course reversal of the entry (in a parallel or
tear-drop entry), the GPS again provided a turn-to heading countdown
message and a graphic on the moving map.


--
Peter