The G5 is excellent. Would be nice if Garmin could have added a temperature input to give TAS but for the price one really can't complain.
Put one into an AA5 last summer. Our backup AI needed replacing and, after looking at prices and options, decided to make our primary (vacuum) AI the backup and install the G5 as the new primary.
Very much enjoyed flying with it until some @#£&+*@# taxied into my (parked) aircraft. It'll be back up again soon. Have also thought of installing a second G5 as an HSI. The two together don't quite give the functionality of an Aspen but it's a great improvement over the standard vacuum gauges.