I've been quite happy with the Lepa G1200 (and, presumably, the G1600) for powering my cubes.  The G1200 runs 3 with no trouble at all, no issues with startup surge, and I'm quite confident it would run another one or two cubes as well.  They're expensive PSUs, but JonnyGuru approved, and quite efficient (peaking over 90% efficiency at about a half load, which is part of why I have such a large one).