It sounds great, but I fear it falls between the same two stools that all others have.
Either it puts out at least 70watts, making it ICAO compliant and powerful enough to be useful, or it is light, cheap and safe to use at less than wing tip distance away from the pilot of a non metalic aircraft.
Everything so far has been one or the other.
One of my main concerns about Mode S is that sooner or later the DfT will realise that the only way they can implement it is to envoke a massive radar/aerial installation programe, one that will rival the mobile phone network. The cost would be £billions and the EU saying that we keep hearing, "the user pays", will result in none of us being able to afford to fly.
I would still be interested in the specs.