  The nature of the dynamical quantum phase transition between the many-body
localized (MBL) phase and the thermal phase remains an open question, and one
line of attack on this problem is to explore this transition numerically in
finite-size systems. To maximize the contrast between the MBL phase and the
thermal phase in such finite-size systems, we argue one should choose a Floquet
model with no local conservation laws and rapid thermalization to "infinite
temperature" in the thermal phase. Here we introduce and explore such a Floquet
spin chain model, and show that standard diagnostics of the MBL-to-thermal
transition behave well in this model even at modest sizes. We also introduce a
physically motivated spacetime correlation function which peaks at the
transition in the Floquet model, but is strongly affected by conservation laws
in Hamiltonian models.
