After a lot reading. I agree with you that EchoUAT is a solid and cheaper option. But it's so hard to find it in the market.
GDL-82 only give ADBS-out
Navworx ADS600-B is way out of my budget
The echoUat is awesome with the AFS 4500. You will get traffic on the 4500 screen. Other units that talk to the 4500 is the Navworks if you can find one.
Wouldn't rule out Navworx on price. Some have sold cheap on this site. Put up a WTB in classifieds for any / all of these devices and see what you get. You may need a different "in" depending on your desired display.
If having just ADSB-out is an option. Do you think upgrading GTX 327 to 330ES would be the easy way?
Or maybe a Stratus ESG transponder. I have not used one, but I believe it has ADS-B out and WAAS GPS. Used they go for about $2500.00. If your 327 is in good shape it should sell for $700-$800 at least making the upgrade only about $1700 or so.....
PM sent on cheap ads b
I have a used ads ads b offered the original poster