Super-FRS, highly homogeneous transmission tracking detectors are crucial to tag the momentum of the ion/fragment beam. A GEM-TPC detector, whose design combines two major concepts in modern gas-filled detectors [...] generations (prototypes) have been constructed and tested in 2011, 2012 and 2014 with relativistic ion beams [1]. The lastest has a twin configuration, i.e. two GEM-TPC detectors flipped (with the electric [...] of the digital readout electronics GMX based on NYXOR and DNF boards was develped and tested with ion beams [2]. [1] F. Garcia et al., GSI Scientific Report (2014) p. 140. Twin GEM-TPC detector prototype