The problem for me is that there is no data output port and so traffic can't be displayed on a GPS screen (for example). I think that whoever comes up with a cheap, directional, hardwired PCAS system with hull mounted antenna and data output port will have a great product.
The cheapest active traffic system that I have come across is the Garmin GTS-800 which cost around £6000 plus fitting when I was investigating it....I see Gulf Coast Avionics have them for $13,995 installed.