The Enigma box is for Light Sport Aircraft, Experimentals and like. It is a VFR solution, not IFR. Probably won't be allowed in standard certified aircraft. Looks to me like it is aimed at the US market where TABS WILL be allowed for Experimentals and Light Sport.
They are already competing against at least two products I know of that are TABS approved GPS units for around US$700 which can drive ADSB capable transponders. One is a Garmin unit. The cost of the TSO'd transponder has been the issue.
It also isn't "portable". You'll need a transponder antenna and a GPS antenna on the outside of the aircraft. Likely the installation wiill need "approval" and/or "certification". No bets as to whether CASA and ASA will countenance TABS devices in Australia.
Flarm will likely only help you in the circuit. The range is short, uncertain and the system suffers from airframe shielding due to the frequency and the low power transmitter. Also needs a Flarm equipped target. PowerFlarm will detect transponder Mode C (range and altitude only, no bearing) and ADSB targets but doesn't advertise its presence to those.