To take advantage of the FAA rebate program I shopped around and decided to order the ADS600B in/out with WiFi, Transmon unit and a UAT antenna only for about $2219 as I already have an external GPS (Garmin GA35) for my Cherokee, this was Aug 23rd/2016. After 6 weeks pased and no unit, Navworx told me they were having certification issues and would have a solution by mid Oct. Then the FAA AD problem was issued and I called Navworx many times and sent several email to cancel order and a full refund - no answers - NO RESPONSES. Oct 25, I filed a bank claim against them and I will get refunded by the bank in 60 days. I contacted FreeFlight Systems and got a great deal from Ashley (sales mgr) and ordered a FLD-978-XVRL IN & OUT with WiFi and UAT antenna for $2621+$25 ship = $2646- $500 ( FAA rebate) = $2146 total without external GPS. FreeFlight shipped out in 8 days! All I need is about 15 feet of multi- wire cable (spruce) and I'm good. Too bad Navworx is taking money and not providing a product or returns with NO CUSTOMER SERVICE. Their loss!