The Dynon ADSB IN solution works pretty well as far as I can tell.
I say “as far as I can tell” because the unit (which is made for Dynon by Uavionics) has a filtering algorithm built in to its software that normally doesn’t paint aircraft unless they are a potential threat. While this might be useful for display clarity in a congested traffic situation, it deprives you of the ability to manually confirm all other aircraft are painted. This is disconcerting sometimes.
There is a work - around for this with the current software that gives you all targets but it’s provided by accident not design.
Furthermore, I wonder if there should be a compulsory standard radio call for announcing that you have acquired an aircraft on ADSB? This is the equivalent of “traffic sighted”. When arranging or confirming separation, I call ‘Got you on ADSB’ and have had ‘got you on TCAS” or ADSB back. IMHO you need to do this especially with RPT as part of confirming that both of you agree on how you are going to separate.