  In light of recent tension between theory and experiment for the process ttW
in the 3l channel, we present a phenomenological study of carefully chosen
observables. We employ the full off-shell results at NLO QCD for ttW+ and ttW-
to build the cross section ratio, an observable which is expected to exhibit
enhanced perturbative stability. Furthermore, we also revisit the charge
asymmetries of the top and its decay products at the fiducial integrated level.
The impact of modelling is investigated for all observables.
