I have a GX 55 and have used it for several years now. In order to work correctly you need to purchase the 4MB data card. These can be purchased off ebay for 12 -20 bucks vs Jeppesen for 125.00. If I were in the market today, I would use a portable until I could save enough for a 430 waas. All the approaches seem to be heading in the waas direction and as most know, waas approaches now out number ILS systems. Keep in mind the install is where the costs come into play. When I make my move on a 430, I am also going to have a new audio panel and transponder installed. I want to remove every old wire I can replace so, circuit breakers will be replaced too. It doesn't stop there as all the radio wires and jacks need to be shielded and the old coax has to be replaced with the new stuff. When you begin adding up the other expenses, it really get into some cash. For now it is just gas, oil and sectionals.